fix(content-marking): reject boolean assertion version

src/agentrust_trace/content_marking.py

@@ -136,9 +136,10 @@ def verify_assertion(assertion: dict[str, Any], record_bytes: bytes) -> dict[str
     data = assertion.get("data")
     if not isinstance(data, dict):
         raise ContentMarkingError("assertion has no data object")
-    if data.get("version") != ASSERTION_VERSION:
+    version = data.get("version")
+    if isinstance(version, bool) or version != ASSERTION_VERSION:
         raise ContentMarkingError(
-            f"unknown assertion version {data.get('version')!r}; expected {ASSERTION_VERSION}. "
+            f"unknown assertion version {version!r}; expected {ASSERTION_VERSION}. "
             "An unknown version is rejected rather than parsed best-effort."
         )
 

tests/test_content_marking_version_boundary.py

@@ -0,0 +1,46 @@
+from __future__ import annotations
+
+import json
+
+import pytest
+
+from agentrust_trace.content_marking import ContentMarkingError, build_assertion, verify_assertion
+
+URL = "https://registry.example/records/abc123.json"
+
+
+def _record_bytes() -> bytes:
+    return json.dumps(
+        {
+            "eat_profile": "tag:agentrust-io.com,2026:trace-v0.2",
+            "iat": 1760000000,
+            "subject": "spiffe://example.org/agent/image-bot",
+            "data_class": "public",
+        }
+    ).encode()
+
+
+def _assertion_with_version(version):
+    raw = _record_bytes()
+    assertion = build_assertion(raw, url=URL)
+    assertion["data"]["version"] = version
+    return assertion, raw
+
+
+def test_integer_version_one_is_accepted() -> None:
+    assertion, raw = _assertion_with_version(1)
+    assert verify_assertion(assertion, raw)["subject"] == "spiffe://example.org/agent/image-bot"
+
+
+@pytest.mark.parametrize("version", [True, False, "1", None, 2])
+def test_non_v1_version_values_are_refused(version) -> None:
+    assertion, raw = _assertion_with_version(version)
+    with pytest.raises(ContentMarkingError, match="unknown assertion version"):
+        verify_assertion(assertion, raw)
+
+
+def test_boolean_true_cannot_alias_integer_version_one() -> None:
+    assertion, raw = _assertion_with_version(True)
+    with pytest.raises(ContentMarkingError) as excinfo:
+        verify_assertion(assertion, raw)
+    assert "expected 1" in str(excinfo.value)