diff --git a/libexif/apple/mnote-apple-entry.c b/libexif/apple/mnote-apple-entry.c
index e24eda8..6740d8e 100644
--- a/libexif/apple/mnote-apple-entry.c
+++ b/libexif/apple/mnote-apple-entry.c
@@ -132,12 +132,16 @@ mnote_apple_entry_get_value(MnoteAppleEntry *entry, char *v, unsigned int maxlen
 	    }
 	    break;
 	case EXIF_FORMAT_RATIONAL:
+	    if (size < exif_format_get_size (EXIF_FORMAT_RATIONAL)) return NULL;
+	    if (entry->components < 1) return NULL; /* FIXME: could handle more than 1 too */
 	    vr = exif_get_rational (data, entry->order);
 	    if (!vr.denominator) break;
 	    snprintf (v, maxlen, "%2.4f", (double) vr.numerator /
 					    vr.denominator);
 	    break;
 	case EXIF_FORMAT_SRATIONAL:
+	    if (size < exif_format_get_size (EXIF_FORMAT_SRATIONAL)) return NULL;
+	    if (entry->components < 1) return NULL; /* FIXME: could handle more than 1 too */
 	    vsr = exif_get_srational (data, entry->order);
 	    if (!vsr.denominator) break;
 	    snprintf (v, maxlen, "%2.4f", (double) vsr.numerator /