The project MCP server approval prompt now offers an "always allow" option that saves approved servers to `config.toml`, with an all/custom/none picker so you choose exactly which servers to persist. --- The project-level MCP server approval prompt (`dcode` startup) only offered per-session, fingerprint-based trust. This adds an "always allow" choice (`a`/`always`) that persists approved servers to `[mcp].enabled_project_servers` in the user-level `config.toml`, so they load by name on future runs without re-prompting — even if the config content changes. Rather than presuming the whole list, "always allow" now lets you choose *which* servers to save via an `[a]ll / [c]ustom / [n]one` menu. `custom` reprints the servers numbered and accepts a `1,3`-style selection; a single prompted server skips the menu. The writer only ever touches the user's home `config.toml` (never a repo file), preserving the boundary that a committed `.mcp.json` can't self-approve. --- ## ⚠️ Breaking change (migration) This branch evolved past the original design above. As shipped, "always allow" persists **fingerprint-scoped** approvals under `[mcp].enabled_project_server_approvals` (bound to project root + server-definition fingerprint, so a changed command/URL re-prompts) via an arrow-key checkbox picker — not the flat, name-based `[mcp].enabled_project_servers` list or the `all/custom/none` text menu described above. Consequences for anyone who adopted the previous per-server trust feature (`[mcp].enabled_project_servers`, shipped in `0.1.33`/`0.1.34`): - The legacy `[mcp].enabled_project_servers` TOML key is now **ignored** (a debug-only log warns; the key is preserved on write, not deleted). - The env override `DEEPAGENTS_CODE_ENABLED_PROJECT_MCP_SERVERS` is renamed to `DEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERS` (still name-based and project-agnostic — the explicit escape hatch). - **Interactive `dcode`:** affected servers move back to the approval prompt; re-approve once with `a`. Safe, mildly annoying. - **Non-interactive / `dcode mcp login`:** affected servers silently stop loading (no prompt in these surfaces). Re-run `dcode` in the project to persist a scoped approval, or set `DEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERS` to keep the old name-based behavior. This is fail-closed (no server loads with *less* scrutiny than before), so it is a safety-preserving break. Made by [Open SWE](https://openswe.vercel.app/agents/6cb9d698-5a31-5568-306a-9ff7a3f4356b) --------- Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
67 KiB
Threat Model: deepagents-code
Note:
deepagents-codewas forked fromdeepagents-cliat v0.1.0. References to "the CLI" throughout this document describe thedeepagents-coderuntime.
Generated: 2026-03-28 | Commit:
e859077f| Scope: libs/code only
Disclaimer: This threat model is automatically generated to help developers and security researchers understand where trust is placed in this system and where boundaries exist. It is experimental, subject to change, and not an authoritative security reference — findings should be validated before acting on them. The analysis may be incomplete or contain inaccuracies. We welcome suggestions and corrections to improve this document.
Scope
In Scope
deepagents_code/— all Python source modules shipped as thedeepagents-codepackage- CLI entry point (
main.py,__init__.py) - Interactive TUI (
app.py,tui/textual_adapter.py,tui/widgets/) - Non-interactive pipeline runner (
client/non_interactive.py) - Agent creation (
agent.py) - Built-in tools (
tools.py:http_request,web_search,fetch_url) - MCP config loader and per-server allow/deny lists (
mcp_tools.py,model_config.py) - Hook dispatcher (
hooks.py) - Sandbox integration factory (
integrations/sandbox_factory.py,integrations/sandbox_provider.py) - Session persistence (
sessions.py) - Configuration system (
config.py,model_config.py) - Unicode/URL safety helpers (
unicode_security.py) - LangGraph dev server subprocess management (
client/launch/server.py,client/launch/server_manager.py,server_graph.py) - Remote agent client (
client/remote_client.py) - Local context middleware (
local_context.py) - Custom subagent loader (
subagents.py,agent.py:load_async_subagents) - Conversation offload (
offload.py) - Skill management (
skills/commands.py)
Out of Scope
libs/deepagents/(SDK library) — separate package with its own threat modellibs/acp/,libs/evals/,libs/partners/— separate packagestests/— not shipped code; used during analysis onlyscripts/,examples/— developer tooling, not shipped- Deployment infrastructure, CI/CD pipelines
- LLM provider behavior (model outputs, jailbreaks) — user-controlled
- Sandbox provider internals (Daytona, LangSmith, Modal, Runloop, AgentCore) — third-party
- LangGraph server internals — consumed as a subprocess dependency
Assumptions
- The CLI runs locally on the user's machine; the user is a developer who invoked
deepagentsthemselves. - The project provides the HITL approval framework; users control model selection, API keys, and whether to disable approval gates.
~/.deepagents/is only writable by the authenticated local user — no multi-user shared home directories.- Sandbox backends are trusted third-party services. CLI responsibility ends at correctly constructing and dispatching requests to them.
- LangSmith tracing, if enabled, is user-opted-in via environment variables.
- The LangGraph dev server subprocess binds to
127.0.0.1by default (client/launch/server.py:_DEFAULT_HOST) and is ephemeral — started and stopped per CLI session. DA_SERVER_*environment variables are readable only by the CLI process and its child server subprocess (OS process isolation assumption).- Users who set
class_pathinconfig.tomlaccept the same trust model aspyproject.tomlbuild scripts — they control their own machine.
System Overview
deepagents-code is a terminal-based AI coding assistant. It wraps the deepagents SDK in an interactive TUI (Textual) and a headless non-interactive mode. Both modes route agent execution through a local langgraph dev subprocess: the CLI spawns a server, passes configuration via DA_SERVER_* environment variables, and communicates via a RemoteAgent HTTP+SSE client. The agent receives user prompts, reasons with a configurable LLM, and executes side-effecting tools (file read/write, shell commands, web search, HTTP requests) subject to a human-in-the-loop (HITL) approval gate. Sessions are persisted in a local SQLite checkpoint database. Users can extend the agent with MCP servers (stdio processes or remote HTTP/SSE endpoints), hooks (event-driven subprocesses), custom subagents (AGENTS.md files in .deepagents/agents/), async remote subagents (LangGraph deployments configured in config.toml), and pluggable sandbox backends for remote code execution.
Architecture Diagram
┌──────────────────────────────────────────────────────────────────────┐
│ User (local machine) │
│ │
│ CLI Args / Env Vars ──► C1: CLI Entry Point (main.py) │
│ │ │
│ ┌────────────────┼─────────────────────┐ │
│ ▼ ▼ ▼ │
│ C2: TUI (app.py) C2b: Non-interactive C13: Config Channel │
│ │ (client/non_interactive.py) (DA_SERVER_* vars) │
│ - - - - - - - - - - TB8: CLI / Server IPC - - - - - │ - - - - - - - │
│ │ ▼ │
│ │ C11: Server Manager (client/launch) │
│ │ │ spawns │
│ │ ▼ │
│ │ C11b: LangGraph Dev Server │
│ │ (client/launch/server.py:ServerProcess) │
│ │ LANGGRAPH_AUTH_TYPE=noop │
│ - - - - - - - - │ - - - - - TB10: RemoteAgent / Dev Server - - - - │
│ │ ▲ │
│ └─►C12: RemoteAgent────┘ (HTTP+SSE on 127.0.0.1) │
│ (client/remote_client.py) │
│ │ │
│ C3: Agent Engine (server_graph.py) │
│ (create_cli_agent, deepagents SDK) │
│ │ │
│ User Prompt ──────────────┘ │
│ │ │
│ - - - - - - - - - TB1: User→Agent Input - - - - - - - - - - - - - │
│ │ │
│ LLM Decision │
│ - - - - - - - - - TB2: LLM → Tool Execution (HITL) - - - - - - - - │
│ │ │
│ ┌──────────┬─────────┬───┴────────┬──────────┬──────────────┐ │
│ ▼ ▼ ▼ ▼ ▼ ▼ │
│ C4:Tools C5:MCP C6:Hooks C8:Sessions C7:Sandbox C14:Async │
│ (file, (procs/ (subprocs (SQLite) (Daytona/ Subagents │
│ shell, remote) hooks.json) Modal/etc.) (LangGraph │
│ HTTP) remotes) │
│ │ │ │ │ │ │
│ - │ - - - - -│- - - - TB3 - - - - -│- - - - - │ - - - - - - -│ - - │
│ │ ▼ ▼ ▼ │ │
│ │ External Local FS Remote External LG │
│ ▼ MCP Server (~/.deep Sandbox Deployment │
│ External (proc/net) agents/) API │
│ Web/APIs │
│ - - - TB4: Web content → Context - - - - - - - - - - - - - - - - - │
│ Tool results re-enter agent context window │
│ - - - TB9: LocalContextMiddleware / Host environment - - - - - - - │
│ C15: LocalContextMiddleware runs bash detect script │
│ │
│ C9: Config System ──► C17: Model Config (class_path → importlib) │
│ (config.toml, .env) │
└──────────────────────────────────────────────────────────────────────┘
Components
| ID | Component | Description | Trust Level | Default? | Entry Points |
|---|---|---|---|---|---|
| C1 | CLI Entry Point | Parses argv, loads config/env, bootstraps session | framework-controlled | Yes | main.cli_main, main.parse_args |
| C2 | TUI / Non-interactive | Textual UI for interactive chat; client/non_interactive.py for headless pipelines (both use RemoteAgent) |
framework-controlled | Yes | app.DeepAgentsApp.run, client.non_interactive.run_non_interactive |
| C3 | Agent Engine | LangGraph agent graph running inside langgraph dev server, assembled by create_cli_agent |
framework-controlled | Yes | agent.create_cli_agent, agent._add_interrupt_on, server_graph.make_graph |
| C4 | Built-in Tools | http_request, web_search (Tavily), fetch_url (HTML→markdown) |
framework-controlled | Partial¹ | tools.http_request, tools.web_search, tools.fetch_url |
| C5 | MCP Loader & Trust | Discovers/loads .mcp.json, validates server configs, applies per-server allow/deny lists + interactive approval |
framework-controlled | No² | mcp_tools.resolve_and_load_mcp_tools, model_config.load_mcp_server_trust_lists, main._check_mcp_project_trust |
| C6 | Hook Dispatcher | Fires subprocess commands on agent lifecycle events | framework-controlled | No³ | hooks.dispatch_hook, hooks._run_single_hook |
| C7 | Sandbox Integration | Creates/destroys remote sandboxes (Daytona, LangSmith, Modal, Runloop, AgentCore) | framework-controlled | No⁴ | integrations.sandbox_factory.create_sandbox |
| C8 | Session Persistence | SQLite checkpoint store for LangGraph thread state | framework-controlled | Yes | sessions.get_db_path, sessions.generate_thread_id |
| C9 | Configuration System | TOML config, env vars, AGENTS.md system prompts, model config |
user-controlled | N/A | config.settings, model_config.ModelConfig, ~/.deepagents/config.toml |
| C10 | Unicode/URL Safety | Detects hidden Unicode, checks URL domain spoofing for approval UI warnings | framework-controlled | Yes | unicode_security.detect_dangerous_unicode, unicode_security.check_url_safety |
| C11 | LangGraph Dev Server | Subprocess running langgraph dev with LANGGRAPH_AUTH_TYPE=noop; managed by ServerProcess |
framework-controlled | Yes⁵ | client.launch.server.ServerProcess.start, client.launch.server.generate_langgraph_json, client.launch.server_manager.start_server_and_get_agent |
| C12 | Remote Agent Client | HTTP+SSE client wrapping RemoteGraph; connects to C11 on localhost |
framework-controlled | Yes⁵ | client.remote_client.RemoteAgent.astream, client.remote_client.RemoteAgent.aget_state |
| C13 | Server Config Channel | Passes CLI config to server subprocess via DA_SERVER_* environment variables |
framework-controlled | Yes | _server_config.ServerConfig.to_env, _server_config.ServerConfig.from_env |
| C14 | Async Subagent Config | Loads remote LangGraph deployment specs from [async_subagents] in config.toml |
user-controlled | No | agent.load_async_subagents |
| C15 | LocalContext Middleware | Runs a bash detection script via backend; injects git/project/env context into system prompt each turn | framework-controlled | Yes⁶ | local_context.LocalContextMiddleware.before_agent, local_context.build_detect_script |
| C16 | Custom Subagent Loader | Reads {dir}/{name}/AGENTS.md YAML frontmatter from .deepagents/agents/ and project .agents/ directories |
user-controlled | No | subagents.list_subagents, subagents._parse_subagent_file |
| C17 | Model Config Loader | Resolves model provider, supports class_path for arbitrary BaseChatModel instantiation via importlib |
user-controlled | N/A | config.create_model, config._create_model_from_class, model_config.ModelConfig.load |
Notes:
http_requestandfetch_urlenabled by default;web_searchrequiresTAVILY_API_KEY.- MCP servers only load if
.mcp.jsonconfig files are present. - Hooks only execute if
~/.deepagents/hooks.jsonexists. - Sandbox mode requires explicit
--sandboxCLI flag. - Both TUI and non-interactive modes now always spawn a local LangGraph dev server and connect via
RemoteAgent. LocalContextMiddlewareis added wheneverLocalShellBackendor an_AsyncExecutableBackendis in use (agent.py:create_cli_agent).
Data Classification
| ID | PII Category | Specific Fields | Sensitivity | Storage Location(s) | Encrypted at Rest | Retention | Regulatory |
|---|---|---|---|---|---|---|---|
| DC1 | API Keys / Credentials | ANTHROPIC_API_KEY, OPENAI_API_KEY, TAVILY_API_KEY, LANGSMITH_API_KEY, LANGGRAPH_API_KEY |
Critical | Process environment only; never written to disk by CLI code | N/A (in-memory) | Process lifetime | All — breach trigger |
| DC2 | Conversation Messages | User prompts, LLM responses, tool args/results | High | SQLite (~/.deepagents/*.db) via LangGraph checkpointer |
No (local file, unencrypted) | Unbounded (session files persist) | GDPR if personal data is discussed |
| DC3 | System Prompt Content | DA_SERVER_SYSTEM_PROMPT env var; custom AGENTS.md contents |
Medium | Process environment (transient); ~/.deepagents/{agent}/AGENTS.md on disk |
No | Config lifetime | None direct |
| DC5 | Offloaded Conversation History | Summarized + raw conversation messages written to sandbox backend | High | Sandbox filesystem at /conversation_history/{thread_id}.md |
Depends on sandbox provider | Sandbox session lifetime | GDPR if personal data is discussed |
Data Classification Details
DC1: API Keys / Credentials
- Fields:
ANTHROPIC_API_KEY,OPENAI_API_KEY,TAVILY_API_KEY,LANGSMITH_API_KEY,LANGGRAPH_API_KEY, and any provider-specific keys in the user's environment. - Storage: Loaded from environment at process start (
config.py). The CLI explicitly stripsLANGGRAPH_CLOUD_LICENSE_KEYand related auth vars from the server subprocess environment (client/launch/server.py:_build_server_env) but passes the remaining env vars (including provider API keys) to the server subprocess viaos.environ.copy(). - Access: Available to both the CLI process and the server subprocess (which inherits the full environment minus stripped vars).
- Encryption: Not encrypted — in-memory process environment only.
- Retention: Process lifetime; cleared on CLI exit.
- Logging exposure: Provider SDK error messages may include partial key information. The CLI does not log keys directly.
- Gaps: API keys are passed to the server subprocess via
_build_server_envwhich doesos.environ.copy()— all keys in the parent's environment become available to the child.
DC2: Conversation Messages
- Fields: Full conversation history (HumanMessage, AIMessage, ToolMessage) stored as LangGraph checkpoint state.
- Storage: SQLite at
~/.deepagents/{agent}/{thread_id}.db(viasessions.get_db_path). - Access: Local filesystem; readable by any process running as the same user.
- Encryption: None — plaintext SQLite.
- Retention: Unbounded — session files persist until manually deleted.
- Logging exposure: Tool call arguments and results (including fetched web content) are in the checkpoint. File contents read by the agent are stored there too.
- Gaps: Unencrypted on disk; no retention policy enforced by the CLI.
DC5: Offloaded Conversation History
- Fields: Timestamped, formatted conversation messages written by
offload.offload_messages_to_backend. - Storage: Sandbox backend filesystem at path
/conversation_history/{thread_id}.mdwherethread_idis a UUID7 (viasessions.generate_thread_id). - Access: Accessible within the sandbox session; depends on provider access controls.
- Encryption: Depends on sandbox provider storage backend.
- Retention: Sandbox session lifetime (destroyed when sandbox is deleted).
- Logging exposure: Contains full message history including tool results.
- Gaps: Thread ID is UUID7 (no path injection risk), but offloaded content is unstructured markdown containing raw conversation data.
Trust Boundaries
| ID | Boundary | Description | Controls (Inside) | Does NOT Control (Outside) |
|---|---|---|---|---|
| TB1 | User Input → Agent Engine | Where user-typed prompts enter the agent graph | Prompt routing, session threading, UI rendering | Prompt content — any text accepted |
| TB2 | LLM Decision → Tool Execution | HITL gate on all side-effecting tool calls | Interrupt map, allow-list check, auto-approve toggle | LLM reasoning; what user approves |
| TB3 | Tool Result → LLM Context | Tool outputs re-enter the context window | Unicode warnings on URLs in args; markdownify HTML conversion | Content of fetched web pages, MCP responses, search results |
| TB4 | MCP Config → Process / Network | .mcp.json triggers subprocess spawn or network connection |
Schema validation; per-server allow/deny lists + interactive approval prompt | What the MCP process does once trusted and running |
| TB5 | Hooks Config → Subprocess | hooks.json commands execute as local subprocesses |
JSON structure validation, 5-second timeout | Command content (user-authored); env vars available to child |
| TB6 | Setup Script → Sandbox Execution | User-supplied script runs inside sandbox at startup | shlex.quote() wrapping; string.Template.safe_substitute |
Script content (user-authored); sandbox network access |
| TB7 | External LLM API → Agent State | LLM API responses drive tool call decisions | LLM client configuration, model selection, request params | LLM output content; provider-side safety |
| TB8 | CLI → Server Subprocess IPC | Config passed from CLI to langgraph dev subprocess via DA_SERVER_* env vars |
ServerConfig.to_env() serialization; env var scoping to parent+child process |
Subprocess environment post-fork; /proc visibility to same-uid processes |
| TB9 | LocalContextMiddleware → Host Env | Bash detect script output (git info, project files, Makefile) injected into system prompt | Script is framework-generated static code; 30s timeout; exit-code check | Content of Makefile, pyproject.toml, git branch names, directory listing |
| TB10 | RemoteAgent → LangGraph Dev Server | CLI communicates with agent via HTTP+SSE on localhost | Server bound to 127.0.0.1 (client/launch/server.py:_DEFAULT_HOST); ephemeral per session |
No authentication (LANGGRAPH_AUTH_TYPE=noop); any localhost process can reach the API |
| TB11 | Config File → Code Execution | class_path in config.toml triggers importlib.import_module(); project/global .env values are loaded into the process environment and can reach Bash startup hooks |
Format validation (module:ClassName); issubclass(BaseChatModel) check; dotenv loading denies shell startup / environment-hijack keys (BASH_ENV, ENV) |
Module-level side effects execute during import; user controls config file; project files in the working directory influence execution |
Boundary Details
TB1: User Input → Agent Engine
- Inside:
app.DeepAgentsApproutes keystrokes to message queue;client.non_interactive.run_non_interactivereads from stdin/argv. Both paths now go throughRemoteAgent.astreamto the server. Session ID assigned per thread (sessions.generate_thread_id). - Outside: Prompt content — the agent accepts any text the user types. No content filtering at this layer (HITL handles downstream tool calls, not prompt intent).
- Crossing mechanism: HTTP POST to
127.0.0.1:{port}viaclient.remote_client.RemoteAgent.astream.
TB2: LLM Decision → Tool Execution Gate (HITL)
- Inside:
agent._add_interrupt_onregisters interrupt configs forexecute,write_file,edit_file,web_search,fetch_url,task,compact_conversation,launch_async_subagent,update_async_subagent,cancel_async_subagent. In non-interactive mode,client.non_interactive._handle_action_requestenforces the shell allow-list viaconfig.is_shell_command_allowed. - Outside: Once the user clicks "approve" (interactive) or a command passes the allow-list check (non-interactive), the tool executes with no further framework-level gating.
- Crossing mechanism: LangGraph HITL interrupt routed through
RemoteAgentSSE stream. - Key note:
auto_approvemode bypasses all HITL approval prompts while still displaying Unicode/URL warnings.
TB3: Tool Result → LLM Context
- Inside:
agent._format_execute_description/_format_fetch_url_descriptionscan tool arguments (not results) for hidden Unicode and suspicious URLs.fetch_urlconverts HTML to markdown viamarkdownifybefore returning. - Outside: The content of tool results (fetched web pages, web search snippets, MCP tool responses,
executestdout) is passed verbatim into the LLM context window. No prompt-injection scanning of results. - Crossing mechanism: LangGraph
ToolMessagereturned to agent graph state; streamed to CLI via SSE.
TB4: MCP Config → Process / Network
- Inside:
mcp_tools._validate_server_configvalidates JSON structure and field types. Project-level servers (stdio and remote) require approval: an interactive prompt (main._check_mcp_project_trust) that offers allow-for-this-session ("y"), remember a chosen subset of servers ("r"), or deny ("N") — unless--trust-project-mcpis set, which trusts the whole config for the run. Whole-config trust is never persisted; it exists only as in-memory run state, set by--trust-project-mcpor by an interactive allow-once/remember decision. The remembered subset governs only what is persisted for future runs — both allow-once and remember load every prompted server for the current session. Persistent "remember" (a.k.a. "always allow") decisions are stored in[mcp].enabled_project_server_approvalswith project root, server name, and server definition fingerprint, so a different project or changed command/URL under the same name requires re-approval. Users can reject individual project server names via[mcp].disabled_project_servers(orDEEPAGENTS_CODE_DISABLED_PROJECT_MCP_SERVERS). There is also an explicit process-wide escape hatch,DEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERS, that approves matching names globally and intentionally bypasses the project/fingerprint binding. Reject wins over approval and over full trust, with one documented exception: if the user'sconfig.tomlis unreadable (see below), any deny defined only there is lost, so a name that is both TOML-disabledand exported inDEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERSsurvives — an accepted footgun (load_mcp_server_trust_listsdocuments it inline) that requires a self-contradicting config plus the explicit dangerous opt-in, and the read error is surfaced to the user. These policies are read bymodel_config.load_mcp_server_trust_listsonly from user-controlled sources — the user-level~/.deepagents/config.toml, the global~/.deepagents/.env, and shell-exported env — never from.mcp.jsonor any repo-committed file, so a committed config cannot self-approve its own servers. In particular, the env forms (DEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERS/..._DISABLED_...) are added toconfig._PROJECT_DOTENV_DENIED_ENV_KEYS, so a committed project.envcannot inject them intoos.environeven though it is loaded at bootstrap. The dangerous enable env var replaces TOML approvals when set, while disabled unions TOML and env so a deny can never be silently emptied by the other source. If the user'sconfig.tomlexists but cannot be read or parsed, the loader fails closed (project configs are treated as untrusted and the error is surfaced) rather than proceeding with an empty deny list. Only scoped-approved, dangerously env-enabled, or fully trusted names survive into the merged config, so a non-approved remote entry is never preflighted and its interpolated headers are never resolved. - Outside: Stdio server
command,args, andenvfields are user-controlled strings passed directly toStdioConnection. Theenvdict from MCP config is forwarded without filtering — users can set arbitrary environment variables (includingPATH,LD_PRELOAD,PYTHONPATH) for the MCP subprocess. - Crossing mechanism:
subprocess.Popen(vialangchain_mcp_adapters) for stdio; HTTP/SSE for remote servers.
TB8: CLI → Server Subprocess IPC
- Inside:
ServerConfig.to_env()serializes all config (model, assistant_id, system_prompt, sandbox settings, cwd, MCP config path, shell-enable flags) toDA_SERVER_*env vars.client.launch.server_manager._apply_server_configwrites these toos.environbeforesubprocess.Popen.client/launch/server.py:_build_server_envstrips cloud auth vars (LANGGRAPH_CLOUD_LICENSE_KEY,LANGSMITH_CONTROL_PLANE_API_KEY,LANGSMITH_TENANT_ID,LANGGRAPH_AUTH). - Outside: The full parent environment including provider API keys flows to the child via
os.environ.copy(). The system prompt string becomesDA_SERVER_SYSTEM_PROMPT. After process start, the env is fixed — no runtime mutation across processes. - Crossing mechanism:
subprocess.Popenenv kwarg; subsequentos.environreads in_server_config.ServerConfig.from_env.
TB9: LocalContextMiddleware → Host Environment
- Inside:
local_context.build_detect_scriptgenerates a static bash heredoc that runs git commands, checks for lock files, reads Makefile headings, and produces a structured markdown summary. Script is static framework code — not constructed from user input. Exit code checked via_handle_detect_result. 30-second timeout. - Outside: The script reads and includes the first 20 lines of
Makefile(_section_makefile) and a directory listing. These file contents are not sanitized before injection into the system prompt. An attacker who can write to the CWD's Makefile can influence the system prompt. - Crossing mechanism:
backend.execute(DETECT_CONTEXT_SCRIPT)→ result appended tosystem_promptviaLocalContextMiddleware._get_modified_request.
TB10: RemoteAgent → LangGraph Dev Server
- Inside: Server bound to
127.0.0.1by default;client/launch/server.py:_DEFAULT_HOST = "127.0.0.1".RemoteAgentonly connects to the URL returned byServerProcess.url. Server is ephemeral — started at session start, stopped at session end. Binds a free ephemeral port by default (client/launch/server.py:_EPHEMERAL_PORT); an explicit port is honored but still falls back to a free port if occupied. - Outside:
LANGGRAPH_AUTH_TYPE=noopdisables all LangGraph server authentication. Any process on localhost that discovers the port can submit requests, read thread state, or inject messages. - Crossing mechanism: HTTP POST/GET to
http://127.0.0.1:{port}usinglanggraph.pregel.remote.RemoteGraph.
TB11: Config File → Code Execution
- Inside:
config._create_model_from_classvalidatesclass_pathformat (module:ClassName), imports the module viaimportlib.import_module(), and checksissubclass(cls, BaseChatModel)before instantiation. - Outside: Module-level code in the imported module executes unconditionally during
import_module(). Theissubclasscheck only runs after import. Any side effects (file I/O, network calls, subprocess spawning) in the module's top-level scope execute before the type check. - Crossing mechanism:
importlib.import_module(module_path)inconfig._create_model_from_class. - Inside (dotenv):
config._load_dotenvloads project and global.envvalues withoverride=Falseand drops shell startup / environment-hijack keys (BASH_ENV,ENV, and related) so a project.envcannot register a script that Bash would source at startup. The preview path (_preview_dotenv_environ) applies the same denylist so a dry-run config change cannot report a value a real reload would reject. - Outside (dotenv): All other
.envkeys are applied to the process environment, and any project file in the working directory (.env,Makefile, build scripts) can still influence execution. See T12.
Data Flows
| ID | Source | Destination | Data Type | Classification | Crosses Boundary | Protocol |
|---|---|---|---|---|---|---|
| DF1 | User | C2 TUI | User prompt text | — | TB1 | Keystrokes / stdin |
| DF2 | C2 TUI | C12 RemoteAgent | Human message + thread config | — | TB1 | Function call |
| DF3 | C12 RemoteAgent | C11 LangGraph Dev Server | Input messages, thread ID | DC2 | TB10 | HTTP POST (localhost) |
| DF4 | C11 LangGraph Dev Server | C12 RemoteAgent | SSE stream (AI responses, tool calls, interrupts) | DC2 | TB10 | HTTP+SSE (localhost) |
| DF5 | C3 Agent | External LLM | System prompt + message history | DC1, DC2 | TB7 | HTTPS / LangChain |
| DF6 | External LLM | C3 Agent | AI response + tool call decisions | — | TB7 | HTTPS / LangChain |
| DF7 | C3 Agent | C4 Tools | Tool call arguments (file/URL/command) | — | TB2 | Function call + HITL |
| DF8 | External | C4 Tools | HTTP response bodies (web/API content) | — | TB3 | HTTPS |
| DF9 | C4 Tools | C3 Agent | Tool results (file content, web pages) | — | TB3 | ToolMessage |
| DF10 | C9 Config | C1 Entry | TOML config, env vars, API keys | DC1 | None | File + environ |
| DF11 | C5 MCP | C3 Agent | MCP tool call results | — | TB3, TB4 | MCP protocol |
| DF12 | C9 Config | C5 MCP | .mcp.json server definitions (command, args, env) |
— | TB4 | File read |
| DF13 | C3 Agent | C8 Sessions | Agent state snapshots | DC2 | None | SQLite async write |
| DF14 | C8 Sessions | C3 Agent | Restored thread state on resume | DC2 | None | SQLite async read |
| DF15 | C9 Config | C6 Hooks | hooks.json command definitions |
— | TB5 | File read |
| DF16 | C3 Agent | C6 Hooks | Event payload (JSON) | — | TB5 | subprocess stdin |
| DF17 | User | C7 Sandbox | Setup script path + content | — | TB6 | File read + execute |
| DF18 | C1 Entry | C11 Server | DA_SERVER_* env vars (config + credentials) |
DC1, DC3 | TB8 | Process environment |
| DF19 | Host FS | C15 LocalContext | Makefile, project file contents (first 20 lines), directory listing | DC3 | TB9 | bash subprocess stdout |
| DF20 | C15 LocalContext | C3 Agent | Project context markdown appended to system prompt | DC3 | TB9 | string append to prompt |
| DF21 | C16 Subagent Loader | C3 Agent | AGENTS.md body (raw text) used as subagent system_prompt | DC3 | None | YAML parse + dict |
| DF22 | C14 Async Config | C3 Agent | AsyncSubAgent specs (URL, graph_id, headers) from config.toml | — | None | TOML parse + dict |
| DF23 | C9 Config | C17 Model Config | class_path string from config.toml |
— | TB11 | TOML parse → importlib |
| DF24 | C5 MCP Config | MCP Subprocess | env dict from .mcp.json forwarded to stdio subprocess |
DC1 | TB4 | subprocess environment |
| DF25 | C3 Agent | C7 Sandbox | Conversation messages for offload | DC5 | TB6 | backend.awrite() |
Flow Details
DF8/DF9: External Web Content → Agent Context
- Data: Arbitrary HTML/JSON from the internet, converted to markdown by
markdownify. Can be megabytes. - Validation: URL domain checked for Unicode spoofing / script mixing (
unicode_security.check_url_safety); displayed as warning in approval dialog. Content not scanned for prompt-injection patterns. - Trust assumption: User approved the fetch. Content is data — but the LLM may interpret adversarial content as instructions.
DF11: MCP Tool Results → Agent Context
- Data: Arbitrary strings/objects from MCP tool calls.
- Validation: MCP config approved at load time (per-server allow-list or interactive prompt). Tool result content not validated after server is trusted.
- Trust assumption: User trusted the MCP server; its outputs are as reliable as the server.
DF18: DA_SERVER_* Env Vars
- Data: Model name, system prompt text, sandbox settings, CWD, MCP config path, shell-enable flags — plus inherited provider API keys.
- Validation: No validation on server side beyond TOML/JSON decoding for structured fields (
_read_env_json). The system prompt and model name are passed through verbatim. - Trust assumption: The server subprocess is trusted with the same access as the CLI process.
DF19/DF20: LocalContextMiddleware Bash Script
- Data: Git branch/status, project language/structure, Makefile first 20 lines, directory listing (up to 20 files), runtime versions.
- Validation: Script exit code checked (
_handle_detect_result). 30-second timeout. Script itself is static framework code — not interpolated from user input. - Trust assumption: Files in the working directory are trustworthy. A malicious Makefile could inject content into the system prompt (requires write access to CWD).
DF23: class_path Config → importlib Code Execution
- Data: Fully-qualified Python class path string (e.g.,
my_package.models:MyChatModel) from[models.providers.<name>]section ofconfig.toml. - Validation: Format check (
module:ClassNamewith:separator). After import,issubclass(cls, BaseChatModel)check. No validation of module contents before import. - Trust assumption: User controls
~/.deepagents/config.toml(same trust model aspyproject.tomlbuild scripts).
DF24: MCP Stdio Env Dict → Subprocess
- Data: Arbitrary key-value pairs from the
"env"field of stdio server definitions in.mcp.json. - Validation: Type check only —
envmust be a dict (mcp_tools._validate_server_config). No filtering of key names or values. Forwarded directly toStdioConnectionwhich passes tosubprocess.Popen. - Trust assumption: User authored or approved the MCP config. Project-level configs go through the approval gate (allow-list or interactive prompt) before loading.
Threats
| ID | Data Flow | Classification | Threat | Boundary | Severity | Validation | Code Reference |
|---|---|---|---|---|---|---|---|
| T1 | DF8, DF9 | — | Prompt injection via fetched web content causes LLM to request harmful actions | TB3 | Medium | Likely | tools.fetch_url, agent._add_interrupt_on |
| T2 | DF7 | — | --shell-allow-list all removes pattern checks; LLM-injected shell commands execute without approval in non-interactive mode |
TB2 | Medium | Verified | config.is_shell_command_allowed, client.non_interactive._handle_action_request |
| T3 | DF7 | — | Unicode-homoglyph URL in LLM-generated tool args deceives user during approval | TB2 | Low | Disproven | unicode_security.check_url_safety, agent._format_fetch_url_description |
| T4 | DF5, DF9 | — | Auto-approve mode bypasses all HITL gates; any LLM-initiated tool call executes | TB2 | Low | Verified | agent.create_cli_agent (auto_approve param), agent._add_interrupt_on |
| T5 | DF13, DF14 | DC2 | Local SQLite checkpoint file tampered with to inject adversarial content into future LLM context | None | Low | Unverified | sessions.get_db_path |
| T6 | DF3, DF4 | DC2 | Unauthenticated LangGraph dev server on localhost can be accessed by any local process | TB10 | Medium | Verified | server._build_server_env, server._DEFAULT_HOST |
| T7 | DF19, DF20 | DC3 | Makefile or project file content injected into system prompt via LocalContextMiddleware | TB9 | Low | Verified | local_context._section_makefile, local_context.LocalContextMiddleware._get_modified_request |
| T8 | DF21 | DC3 | Custom subagent AGENTS.md body used verbatim as system_prompt without content validation | None | Low | Verified | subagents._parse_subagent_file, agent.create_cli_agent |
| T9 | DF23 | — | class_path in config.toml triggers arbitrary Python code execution via importlib.import_module() |
TB11 | Low | Verified | config._create_model_from_class, model_config.ProviderConfig |
| T10 | DF24 | DC1 | MCP stdio subprocess env dict accepts arbitrary keys including PATH, LD_PRELOAD, PYTHONPATH without filtering |
TB4 | Low | Verified | mcp_tools._validate_server_config, mcp_tools._load_tools_from_config |
| T12 | DF10 | — | Project .env sets shell startup-hook variables (BASH_ENV, ENV) that run attacker-controlled scripts when dcode spawns Bash, before any HITL approval |
TB11 | High | Verified | config._load_dotenv, local_context.build_detect_script |
Threat Details
T1: Prompt Injection via Fetched Web Content
- Flow: DF8 (external web) → DF9 (tool result) → C3 Agent context
- Description: When the agent calls
fetch_urlorweb_search, the response body enters the LLM's context window as aToolMessage. A maliciously crafted web page or search snippet can embed natural-language instructions that the LLM may interpret as authoritative commands, leading to unexpected tool call requests in the next turn. - Preconditions: (1) User or LLM-initiated call to
fetch_url/web_searchreaches a malicious page; (2) LLM interprets injected instructions as directives; (3) In interactive mode, user must still approve the resulting tool call.
T2: Shell Allow-List Bypass via SHELL_ALLOW_ALL
- Flow: DF7 (LLM tool call) → C4 Tools (execute)
- Description: When
--shell-allow-list all(orDEEPAGENTS_SHELL_ALLOW_LIST=all) is set,is_shell_command_allowedreturnsTruefor any non-empty command without invokingcontains_dangerous_patterns. In non-interactive mode, any shell command the LLM requests executes unconditionally. Combined with T1, an attacker-controlled page could cause arbitrary command execution. - Preconditions: (1) User has configured
--shell-allow-list all; (2) Non-interactive mode; (3) Successful prompt injection via DF8/DF9.
T3: Unicode Homoglyph URL in Approval Dialog
- Flow: DF7 (LLM-generated fetch_url args) → C2 TUI approval dialog
- Description: An LLM influenced by adversarial input could generate a
fetch_urlcall with a URL containing mixed-script or confusable characters visually identical to ASCII. - Preconditions: LLM generates a confusable URL (requires adversarial steering).
check_url_safetydetects mixed-script domain labels andstrip_dangerous_unicoderemoves invisible BiDi/zero-width characters; warnings displayed in approval dialog. Classified Disproven as a project vulnerability — the UI warnings are the intended control.
T4: Auto-Approve Removes All Execution Safeguards
- Flow: DF7 (all tool calls) when
auto_approve=True - Description: When auto-approve is enabled (via
--auto-approveflag orShift+Tabin TUI), all tool calls includingexecute,write_file,edit_file,fetch_url,launch_async_subagentexecute without user confirmation. - Preconditions: User explicitly enables auto-approve. Default is approval-required.
T5: Local SQLite Checkpoint Tampering
- Flow: DF13/DF14 (session persist/restore)
- Description: LangGraph checkpoints stored in
~/.deepagents/*.dbcontain the full conversation history and agent state. An attacker with local filesystem write access could inject adversarial messages that re-enter the LLM context on session resume. - Preconditions: Attacker has write access to the user's home directory — equivalent to a fully compromised user account.
T6: Unauthenticated LangGraph Dev Server on Localhost
- Flow: DF3/DF4 (CLI ↔ LangGraph dev server)
- Description: The CLI spawns a
langgraph devserver subprocess withLANGGRAPH_AUTH_TYPE=noop(client/launch/server.py:_build_server_env). This disables all server-side authentication. The server binds to127.0.0.1:{port}(a free ephemeral port by default, so it no longer squats the well-knownlanggraph devport 2024). Any local process that discovers the port can: send arbitrary inputs to the running agent thread, read the agent's conversation state (including tool results that may contain file contents or secrets), inject messages into the conversation history, or trigger state updates. The server is ephemeral — it lives only for the duration of the CLI session — but this is the entire attack window. Port discovery is feasible via localhost port scanning or by reading/proc/{pid}/cmdlinewhich contains the--portargument. - Preconditions: (1) Attacker has a local process running as the same user (or as root); (2) Attacker discovers the server port (port scan on localhost, or reads process arguments).
T7: LocalContextMiddleware Injects Host File Contents into System Prompt
- Flow: DF19 → DF20
- Description:
LocalContextMiddlewareruns a bash script (build_detect_script) that reads the first 20 lines ofMakefile(_section_makefile) and a filtered directory listing, then injects this output verbatim into the system prompt on every turn. An attacker with write access to the project's working directory could craftMakefilecontent designed to manipulate the agent's behavior. - Preconditions: Attacker has write access to the
Makefilein the agent's working directory. The agent must be running in that directory (local mode, not sandbox mode).
T8: Custom Subagent Body Used as System Prompt Without Validation
- Flow: DF21
- Description:
subagents._parse_subagent_filereads AGENTS.md files from.deepagents/agents/{name}/AGENTS.mdand project-level.agents/{name}/AGENTS.md. The markdown body after the YAML frontmatter is used verbatim as the subagent'ssystem_prompt. No content filtering is applied. - Preconditions: Attacker has write access to
~/.deepagents/agents/or the project's.agents/directory. User or LLM must invoke the malicious subagent via thetasktool.
T9: Arbitrary Python Code Execution via class_path Config
- Flow: DF23 (config.toml → importlib)
- Description: The
class_pathfield in[models.providers.<name>]config triggersimportlib.import_module()inconfig._create_model_from_class. While the imported class is validated as aBaseChatModelsubclass, module-level code executes unconditionally during import — before the type check runs. A malicious or compromisedconfig.tomlpointing to a hostile module causes arbitrary code execution at model initialization time. This applies to bothclass_pathand the_load_provider_profilespath that usesexec_module()to load_profiles.pyfrom provider packages. - Preconditions: Attacker has write access to
~/.deepagents/config.tomlAND a malicious Python package installed in the user's environment (or onsys.path). The code comments document this as intentional: "same trust model aspyproject.tomlbuild scripts — the user controls their own machine."
T10: MCP Stdio Env Dict Forwarded Without Filtering
- Flow: DF24 (MCP config → subprocess environment)
- Description: The
"env"field in stdio MCP server definitions (.mcp.json) accepts an arbitrary key-value dict.mcp_tools._validate_server_configonly checks that the field is a dict — it does not filter key names or values. The dict is forwarded directly toStdioConnection(env=...)which passes it to the subprocess. An attacker who can modify a project-level.mcp.jsoncould setPATHto redirect command resolution,LD_PRELOADto inject shared libraries, orPYTHONPATHto hijack Python imports in the MCP subprocess. - Preconditions: (1) Attacker has write access to a project-level
.mcp.json; (2) The project MCP config must be approved by the user (the interactive prompt,--trust-project-mcp, or the server approved via[mcp].enabled_project_server_approvals/ theDEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERSenv var). For user-level~/.deepagents/.mcp.json, the attacker already has home directory write access. Note: theenvdict from MCP config is passed toStdioConnection— whether it replaces or merges withos.environdepends on thelangchain_mcp_adapterslibrary implementation.
T11: Auto-Installed ripgrep Binary from Upstream Release
- Flow: Download performed by
managed_tools.ensure_ripgrepwhenrgis not onPATH— either on first run, or eagerly at install time viadcode tools install(invoked byscripts/install.sh). - Description: Without a system
rg, Deep Agents Code fetches the pinned ripgrep release tarball fromgithub.com/BurntSushi/ripgrep/releases/..., verifies it against an in-tree SHA-256 (RIPGREP_ASSETS), extracts it under aTemporaryDirectory, and atomically moves the binary into~/.deepagents/bin/rg. The binary then runs unsandboxed, inheriting the same trust as a user-installedrg(the SDK invokes it viasubprocess.run(["rg", ...])). The same verified path backs thedcode tools installverb, so the install script reuses it rather than re-encoding the version + checksum table in bash. - Mitigations: (1) SHA-256 verified against the pinned hash table before move — a mismatch aborts the install and leaves
BIN_DIRclean. (2) Network egress is limited togithub.com. (3) Opt-out viaDEEPAGENTS_CODE_OFFLINEfor air-gapped environments, orDEEPAGENTS_CODE_RIPGREP_INSTALLER=systemto defer to the OS package manager instead of the managed binary. (4) Pinned version + checksums are bumped in-tree, so a compromised upstream release is detected on the next Deep Agents Code release rather than silently propagating. (5) Atomic move-into-place avoids partial installs when concurrent CLI invocations race. (6) The eager install-script path is non-sudo(no system package manager is invoked in the defaultmanagedmode). - Preconditions: User has not installed
rgvia their package manager,DEEPAGENTS_CODE_OFFLINEis unset,DEEPAGENTS_CODE_RIPGREP_INSTALLERis notsystem, and the host can reachgithub.com. The pinned SHA-256 inRIPGREP_ASSETSwould need to be incorrect (a supply-chain compromise of the deepagents-code release) for a tampered binary to be installed.
T12: Project .env Injects Shell Interpreter Startup Hooks
- Flow: DF10 (project
.env→ process environment) → bash subprocess startup (DF19) - Description:
config._load_dotenvdiscovers the nearest project.envby walking up from the working directory and applies its values to the process environment (override=False, so shell-exported values still win). Bash treats several environment variables as startup hooks —BASH_ENVandENVname a file that is sourced when a non-interactive shell starts. Because Deep Agents Code runs its own local-context detection through Bash at startup (local_context.build_detect_script) and spawns shells for theexecutetool, a project.envthat sets one of these keys could run attacker-controlled scripts inside thedcodeprocess before any model-requested tool call or HITL approval prompt. The broader trust boundary is that runningdcodein a project directory lets that project influence the process environment. - Preconditions: (1) User launches
dcodein a directory containing an attacker-controlled.env(for example, a freshly cloned untrusted repository); (2) the.envsets a shell startup-hook key that is not already exported in the user's shell (dotenv usesoverride=False).
Input Source Coverage
| Input Source | Data Flows | Threats | Validation Points | Responsibility | Gaps |
|---|---|---|---|---|---|
| User direct input | DF1, DF2 | None (TB1) | None — prompts accepted verbatim | User | No content filtering — intentional; HITL gates downstream tool calls |
| LLM output | DF6, DF7 | T1, T2, T3, T4 | HITL gate; shell allow-list; Unicode/URL warnings on tool args | Project | LLM-generated tool args not scanned for injection beyond Unicode/URL |
| Tool/function results | DF9, DF11 | T1 | Unicode warning on URL args; markdownify HTML conversion |
Shared | Tool results pass to context without prompt-injection scan |
| URL-fetched content | DF8, DF9 | T1 | check_url_safety on URL arg; HTML→markdown conversion |
Shared | Markup-embedded instructions survive markdownify; no LLM-layer guardrail |
| Configuration | DF10, DF12, DF15, DF23 | T9, T10, T12 | Dotenv shell-env precedence; TOML schema; MCP schema + allow/deny lists; JSON structure check; class_path format check |
User | Project .env can set shell startup-hook vars; class_path executes module code before type check; MCP env dict unfiltered |
| Session restore | DF14 | T5 | OS file permissions; SQLite | Project | Unencrypted at rest |
| Server IPC (env vars) | DF18 | T6 | ServerConfig serialization; parent env passed to child |
Project | Provider API keys flow to server subprocess; system prompt in env |
| Host environment | DF19, DF20 | T7 | Static script; exit code check; 30s timeout | Shared | Makefile content injected into system prompt without sanitization |
| Custom subagents (FS) | DF21 | T8 | yaml.safe_load; HITL on task tool |
User | Subagent body text not content-filtered |
| Async subagent config | DF22 | None direct | TOML parse; type validation in load_async_subagents |
User | URL and headers for remote subagents are user-controlled; no URL validation |
| MCP subprocess env | DF24 | T10 | Dict type check only (_validate_server_config) |
User | No key/value filtering; arbitrary env vars forwarded to subprocess |
| Offloaded history | DF25 | None direct | Thread ID is UUID7 (no path injection); backend handles storage | Shared | Raw conversation content written to sandbox filesystem |
Out-of-Scope Threats
Threats that appear valid in isolation but fall outside project responsibility because they depend on conditions the project does not control.
| Pattern | Why Out of Scope | Project Responsibility Ends At |
|---|---|---|
| Prompt injection leading to arbitrary code execution (interactive mode) | In interactive mode, every side-effecting tool call requires explicit user approval via the HITL dialog. The user is the final gatekeeper. | Providing HITL for all side-effecting tools (agent._add_interrupt_on) and Unicode/URL warnings in the approval dialog. |
API key exfiltration via LLM-directed http_request |
http_request requires HITL in interactive mode. Keys it could exfiltrate are user-supplied env vars. In non-interactive mode, user has opted into autonomous operation. |
Providing HITL gate for HTTP tools. Users control which env vars are in scope. |
| Malicious MCP server injecting prompt instructions | Users configure MCP servers and explicitly trust project-level configs. Once trusted, MCP tool outputs are data from a system the user controls. | Interactive approval prompt + per-server allow/deny lists for project-level configs (main._check_mcp_project_trust, model_config.load_mcp_server_trust_lists). |
| LLM jailbreak / safety bypass | Model selection and safety configuration are user-controlled. The project routes prompts to the configured LLM but cannot guarantee model behavior. | Correctly routing prompts to the configured LLM; applying the system prompt from agent.get_system_prompt. |
| Sandbox provider security vulnerabilities | Daytona, LangSmith, Modal, Runloop, and AgentCore are third-party services. Their internal security is not this project's responsibility. | Correctly initializing sandbox sessions via integrations.sandbox_factory.create_sandbox. |
| Hook commands doing harmful things | Hooks in ~/.deepagents/hooks.json are 100% user-authored. The payload is data-only (JSON on stdin). |
JSON structure validation (hooks._load_hooks); 5-second timeout. |
| Async subagent traffic interception / MitM | Async subagents connect to user-configured LangGraph deployment URLs. The project does not control those endpoints or their TLS certificates. | Accepting URL/headers from user config and passing them to the LangGraph SDK (agent.load_async_subagents). |
| LangGraph dev server port enumeration / discovery | Discovering the local dev server port requires local access. Port scanning localhost is a general OS security concern, not a framework vulnerability. | Binding to 127.0.0.1 by default (server._DEFAULT_HOST); ephemeral server lifetime; OS-assigned ephemeral port (server._EPHEMERAL_PORT) is not predictable across runs. |
.env file from parent directory changes app/API configuration |
config._find_dotenv_from_start_path walks up the directory tree to find .env files. Discovering ordinary configuration values (API keys, DEEPAGENTS_CODE_* settings) this way is standard python-dotenv behavior, and the user controls their filesystem. The code-execution implication of a project .env (shell startup hooks) is tracked in-scope as T12. |
Finding .env from the project root (config._find_dotenv_from_start_path); override=False by default (existing env vars preserved); shell startup / environment-hijack keys (BASH_ENV, ENV) denied during dotenv loading. |
Rationale
Prompt injection in interactive mode: The HITL interrupt means every file write, shell command, web search, URL fetch, task delegation, and async subagent action shows the user a confirmation dialog with full tool arguments. Even a successful prompt injection can only execute what the user explicitly approves. The project's responsibility is to make that dialog accurate — hence the Unicode/URL warning layer in unicode_security.py.
LangGraph dev server without auth: The LANGGRAPH_AUTH_TYPE=noop setting is intentional for local dev server use. Adding authentication would require users to manage tokens for a locally-spawned ephemeral process, creating more friction than security benefit in this context. The 127.0.0.1 binding limits exposure to the local machine. T6 documents this as an accepted risk for the threat model.
Custom subagent system prompts: Subagent definitions in .deepagents/agents/ are user-authored files. The framework correctly treats them as user-controlled content. The HITL gate on task tool calls ensures the user approves subagent delegation before it occurs.
class_path code execution: This follows the same trust model as pyproject.toml build scripts — the user edits their own config file on their own machine. The issubclass(BaseChatModel) check provides a post-import guard, though module-level side effects execute before it. Documented as intentional in model_config.py.
Investigated and Dismissed
| ID | Original Threat | Investigation | Evidence | Conclusion |
|---|---|---|---|---|
| D1 | Unsafe msgpack deserialization in langgraph checkpoint loading | Verified fix status — confirmed fixed and closed upstream. | Users on current langgraph versions are not exposed. |
Upstream langgraph has patched the unsafe msgpack deserialization. No longer an active risk. |
| D2 | Unicode URL homoglyph as project vulnerability | Traced check_url_safety + strip_dangerous_unicode + format_warning_detail → approval dialog display |
unicode_security.check_url_safety, agent._format_fetch_url_description |
Warning system is the intended control — the project correctly surfaces the risk to the user in the approval dialog. Not a project vulnerability; classified as mitigated by design (UI warning). |
| D3 | SSRF via http_request / fetch_url to internal services |
Traced tools.http_request and tools.fetch_url — no URL scheme or host blocklist. However, both tools require HITL approval in interactive mode. In non-interactive mode, only shell commands are auto-approved via the allow-list; HTTP tools still go through the HITL interrupt gate. |
tools.http_request, tools.fetch_url, agent._add_interrupt_on |
Not a project vulnerability in isolation — the HITL gate is the intended control for all HTTP tool calls. The user sees the full URL before approving. SSRF is only reachable if the user approves the request (interactive) or enables auto-approve (explicit opt-in). Classified as out-of-scope for the same reason as prompt injection in interactive mode. |
| D4 | Offload path injection via thread_id | Checked sessions.generate_thread_id — returns UUID7 string (alphanumeric + hyphens only, no path separators). |
sessions.generate_thread_id, offload.offload_messages_to_backend |
Thread IDs are UUID7 strings generated by the framework. No user-controlled path components reach the file path. Not exploitable. |
Revision History
| Date | Author | Changes |
|---|---|---|
| 2026-03-10 | langster-threat-model (automated) | Initial threat model |
| 2026-03-27 | langster-threat-model (automated) | Deep expansion: added C11-C16 (server subprocess, RemoteAgent, LocalContextMiddleware, async subagent config, custom subagent loader); added TB8-TB10 (CLI/server IPC, LocalContext/host env, RemoteAgent/dev server); added DF18-DF22; added T6 (unauthenticated dev server), T7 (Makefile injection), T8 (subagent body injection); updated T5 (upstream msgpack fix confirmed); added data classification; added Investigated and Dismissed section; updated architecture diagram to reflect server-subprocess model |
| 2026-03-28 | langster-threat-model (automated) | Deep validation pass: added C17 (Model Config Loader with class_path), TB11 (Config→Code Execution); added DC5 (offloaded conversation history); added DF23-DF25 (class_path flow, MCP env dict flow, offload flow); added T9 (class_path arbitrary code execution), T10 (MCP env dict unfiltered); added D3 (SSRF dismissed — HITL is intended control), D4 (offload path injection dismissed — UUID7); removed Status column and Mitigations/Residual Risk fields from all threats (open source visibility compliance — mitigation status must not appear in public threat models); updated T6 validation from Likely to Verified (port is deterministic at 2024 default, discoverable via /proc); updated external context (no published advisories found); updated architecture diagram |
| 2026-06-25 | manual update | Added T12 (project .env injects shell interpreter startup hooks) under TB11; extended the TB11 boundary controls and details with the dotenv shell-startup-hook denylist (BASH_ENV, ENV); clarified the .env out-of-scope row to separate ordinary config discovery from the in-scope code-execution implication |
| 2026-06-25 | manual update | Updated T6 and TB10 to reflect the dev server binding an OS-assigned ephemeral port by default (server._EPHEMERAL_PORT) instead of squatting the well-known langgraph dev port 2024; noted unpredictable-port-across-runs as added defense-in-depth in the port-discovery dismissal row |
| 2026-07-08 | manual update | Removed the SHA-256 config fingerprint trust store (mcp_trust.py, ~/.deepagents/.state/mcp_trust.json, DC4). Project MCP trust is now the interactive approval prompt (allow-for-session / always-allow scoped to project root + server-definition fingerprint / deny), the --trust-project-mcp run flag, the [mcp].enabled_project_server_approvals and [mcp].disabled_project_servers lists, and the process-wide DEEPAGENTS_CODE_DANGEROUSLY_ENABLE_PROJECT_MCP_SERVERS name-based escape hatch. The legacy flat [mcp].enabled_project_servers key is ignored. Persisted approvals bind to a server definition's fingerprint rather than a whole-config fingerprint. Updated C5, TB4, T10, the configuration input-coverage row, and the malicious-MCP-server dismissal accordingly |