diff --git a/.jules/sentinel.md b/.jules/sentinel.md
index 9133bba1..59952c50 100644
--- a/.jules/sentinel.md
+++ b/.jules/sentinel.md
@@ -22,3 +22,7 @@
 **Vulnerability:** Server-Side Request Forgery (SSRF) / Local File Inclusion
 **Learning:** Functions that fetch URLs provided via user inputs (e.g., `wait_for_url` fetching `--backend-ready-url` in CI scripts) can inadvertently read local files if they do not validate the scheme. Python's `urllib.request.urlopen` supports `file://` schemes, allowing attackers to access arbitrary file contents from the host machine or sandbox if they can control the URL parameter.
 **Prevention:** Always validate URL inputs to restrict allowed schemes. Check that URLs explicitly start with `http://` or `https://` before fetching them with standard libraries like `urllib`.
+## 2026-06-30 - Prevent SSRF via Unvalidated URL Schemes in API Clients
+**Vulnerability:** Server-Side Request Forgery (SSRF) / Local File Inclusion
+**Learning:** API clients that load configuration from environment variables (e.g., `NOEMA_LLM_API_URL`) can be exploited if the environment is compromised or influenced by external input. `urllib.request.urlopen` supports `file://` schemes, which can allow arbitrary file reads if the URL scheme is not explicitly restricted.
+**Prevention:** Always validate URL schemes for API clients, even when sourced from environment variables. Ensure URLs explicitly start with `http://` or `https://` before making requests to prevent SSRF and local file inclusion.
diff --git a/scripts/ci/noema_review_gate.py b/scripts/ci/noema_review_gate.py
index 1e4661b7..45dad09b 100644
--- a/scripts/ci/noema_review_gate.py
+++ b/scripts/ci/noema_review_gate.py
@@ -267,6 +267,8 @@ def call_llm(repo: str, number: int, pr: dict[str, Any], diff: str, truncated: b
     if not api_url or not api_key:
         print("Noema LLM review unavailable: NOEMA_LLM_API_URL or NOEMA_LLM_API_KEY is not configured.")
         return None
+    if not api_url.lower().startswith(("http://", "https://")):
+        raise ValueError("Invalid NOEMA_LLM_API_URL scheme. URL must start with http:// or https://")
 
     prompt = {
         "role": "user",
@@ -304,7 +306,7 @@ def call_llm(repo: str, number: int, pr: dict[str, Any], diff: str, truncated: b
         },
         method="POST",
     )
-    with urllib.request.urlopen(request, timeout=120) as response:
+    with urllib.request.urlopen(request, timeout=120) as response:  # nosec B310
         raw = response.read().decode("utf-8")
     data = json.loads(raw)
     content = (((data.get("choices") or [{}])[0].get("message") or {}).get("content") or "").strip()
diff --git a/tests/test_noema_review_gate.py b/tests/test_noema_review_gate.py
index 0b333ab3..545a2b45 100644
--- a/tests/test_noema_review_gate.py
+++ b/tests/test_noema_review_gate.py
@@ -198,6 +198,11 @@ def test_call_llm_handles_configuration_and_verdicts(monkeypatch):
     monkeypatch.delenv("NOEMA_LLM_API_KEY", raising=False)
     assert noema.call_llm("owner/repo", 1, pr, "diff", False) is None
 
+    monkeypatch.setenv("NOEMA_LLM_API_URL", "file:///etc/passwd")
+    monkeypatch.setenv("NOEMA_LLM_API_KEY", "secret")
+    with pytest.raises(ValueError, match="Invalid NOEMA_LLM_API_URL scheme. URL must start with http:// or https://"):
+        noema.call_llm("owner/repo", 1, pr, "diff", False)
+
     monkeypatch.setenv("NOEMA_LLM_API_URL", "https://llm.example.test/chat")
     monkeypatch.setenv("NOEMA_LLM_API_KEY", "secret")
     monkeypatch.setenv("NOEMA_LLM_MODEL", "review-model")