diff --git a/docs/VULNERABILITY_CATALOG.md b/docs/VULNERABILITY_CATALOG.md
index 3f568da..f30ee0d 100644
--- a/docs/VULNERABILITY_CATALOG.md
+++ b/docs/VULNERABILITY_CATALOG.md
@@ -7,10 +7,10 @@ from each file's header comment, so this page cannot drift from the source.
 
 ## Totals
 
-- **Test cases:** 105
-- **Expected detections:** 105
-- **`VULNERABLE:` markers:** 189 (individual lines a scanner should flag)
-- **`SAFE:` markers:** 116 (lines a scanner must not flag — the false-positive control group)
+- **Test cases:** 106
+- **Expected detections:** 106
+- **`VULNERABLE:` markers:** 192 (individual lines a scanner should flag)
+- **`SAFE:` markers:** 117 (lines a scanner must not flag — the false-positive control group)
 - **Languages:** 8 — dotenv, go, java, javascript, json, python, ruby, text
 - **CWE categories:** 78 — CWE-20, CWE-22, CWE-78, CWE-79, CWE-89, CWE-90, CWE-94, CWE-95, CWE-113, CWE-117, CWE-129, CWE-190, CWE-201, CWE-203, CWE-208, CWE-209, CWE-256, CWE-287, CWE-288, CWE-291, CWE-295, CWE-306, CWE-307, CWE-319, CWE-321, CWE-327, CWE-329, CWE-330, CWE-338, CWE-345, CWE-346, CWE-347, CWE-352, CWE-362, CWE-377, CWE-384, CWE-400, CWE-441, CWE-460, CWE-472, CWE-475, CWE-480, CWE-488, CWE-489, CWE-502, CWE-506, CWE-509, CWE-512, CWE-521, CWE-525, CWE-532, CWE-598, CWE-601, CWE-602, CWE-611, CWE-613, CWE-614, CWE-639, CWE-643, CWE-681, CWE-693, CWE-759, CWE-776, CWE-798, CWE-862, CWE-863, CWE-915, CWE-916, CWE-918, CWE-922, CWE-942, CWE-943, CWE-1021, CWE-1236, CWE-1321, CWE-1333, CWE-1336, CWE-1357
 
@@ -114,6 +114,7 @@ counts as a detection. See `docs/SCANNER_INTEGRATION.md`.
 | Insecure temp file creation with predictable path | [`insecure-temp-file.py`](../vulns/python/insecure-temp-file.py) | CWE-377 | medium | yes | 3 vuln / 1 safe |
 | LDAP injection via unescaped search filter | [`ldap-injection.py`](../vulns/python/ldap-injection.py) | CWE-90 | high | yes | 1 vuln / 1 safe |
 | Missing authorization check on administrative handler | [`missing-admin-authorization.py`](../vulns/python/missing-admin-authorization.py) | CWE-862 | high | yes | 1 vuln / 1 safe |
+| Login brute force enabled by absent rate limiting | [`missing-login-rate-limit.py`](../vulns/python/missing-login-rate-limit.py) | CWE-307 | high | yes | 3 vuln / 1 safe |
 | Missing range validation for a user-supplied price | [`negative-price-validation.py`](../vulns/python/negative-price-validation.py) | CWE-20 | medium | yes | 1 vuln / 1 safe |
 | Open redirect via unvalidated next parameter | [`open-redirect.py`](../vulns/python/open-redirect.py) | CWE-601 | medium | yes | 2 vuln / 1 safe |
 | Path traversal via unvalidated filename in open() | [`path-traversal-open.py`](../vulns/python/path-traversal-open.py) | CWE-22 | high | yes | 2 vuln / 2 safe |
diff --git a/vulns/VULNERABILITY_CATALOG.json b/vulns/VULNERABILITY_CATALOG.json
index 1ba1548..f511fbb 100644
--- a/vulns/VULNERABILITY_CATALOG.json
+++ b/vulns/VULNERABILITY_CATALOG.json
@@ -2,10 +2,10 @@
   "schema": "threatcrush-testbed-catalog/1",
   "note": "Generated by scripts/generate-catalog.py \u2014 do not edit by hand.",
   "totals": {
-    "test_cases": 105,
-    "expected_detections": 105,
-    "vulnerable_markers": 189,
-    "safe_markers": 116,
+    "test_cases": 106,
+    "expected_detections": 106,
+    "vulnerable_markers": 192,
+    "safe_markers": 117,
     "languages": [
       "dotenv",
       "go",
@@ -1856,6 +1856,31 @@
         27
       ]
     },
+    {
+      "id": "py-missing-login-rate-limit",
+      "file": "vulns/python/missing-login-rate-limit.py",
+      "title": "Login brute force enabled by absent rate limiting",
+      "category": "python",
+      "language": "python",
+      "cwe": "CWE-307",
+      "cwes": [
+        "CWE-307"
+      ],
+      "severity": "high",
+      "expected_detection": true,
+      "description": "A login endpoint has no attempt counter, no per-IP throttle,",
+      "detection_target": "Password comparison or login handler reachable from a",
+      "safe_guard": "Every request handler is wrapped in `if False:` so the code is",
+      "attribution": "line",
+      "vulnerable_lines": [
+        32,
+        35,
+        47
+      ],
+      "safe_lines": [
+        63
+      ]
+    },
     {
       "id": "py-negative-price-validation",
       "file": "vulns/python/negative-price-validation.py",
diff --git a/vulns/python/missing-login-rate-limit.py b/vulns/python/missing-login-rate-limit.py
new file mode 100644
index 0000000..2713569
--- /dev/null
+++ b/vulns/python/missing-login-rate-limit.py
@@ -0,0 +1,72 @@
+"""
+@id py-missing-login-rate-limit
+@test-case Login brute force enabled by absent rate limiting
+@cwe CWE-307
+@severity high
+@language python
+@expected-detection true
+@description A login endpoint has no attempt counter, no per-IP throttle,
+             and no lockout, so an attacker can try credentials
+             indefinitely. Two variants show the same sink: the first
+             simply returns on a failed password check; the second trims
+             whitespace from the username and password before comparing,
+             which also defeats naive account-lockout keys.
+@safe-guard Every request handler is wrapped in `if False:` so the code is
+            unreachable dead code. No imports of live modules are executed
+            and there is no socket, disk, or file system access.
+@detection-target Password comparison or login handler reachable from a
+                   request with no preceding attempt-count / throttle /
+                   lockout check on the same data-flow path.
+
+NEVER RUN IN PRODUCTION -- intentional test case for scanner validation.
+"""
+
+
+def login_vulnerable(request):
+    """Credential check with no brute-force protection."""
+    if False:
+        # SOURCE: request-supplied credentials
+        username = request.form.get("username")
+        password = request.form.get("password")
+        user = users.get(username)
+        # VULNERABLE: CWE-307 -- unlimited attempts, no throttle or lockout
+        if user and user.get("password") == password:
+            return session_start(user["id"])
+        # VULNERABLE: CWE-307 -- failed attempt is not recorded anywhere
+        return "invalid credentials"
+    return None
+
+
+def login_unsafe_strip_vulnerable(request):
+    """Credential check with an attacker-controlled attempt key."""
+    if False:
+        raw_user = request.form.get("username")
+        raw_pass = request.form.get("password")
+        # SOURCE: whitespace-normalised inputs feed the account lookup
+        user = users.get(raw_user.strip())
+        # VULNERABLE: CWE-307 -- lockout key is derived from user input, so
+        # appending whitespace resets the throttle and bypasses the limit
+        if user and user["password"] == raw_pass.strip():
+            return session_start(user["id"])
+        return "invalid credentials"
+    return None
+
+
+def login_ratelimited_safe(request):
+    """Safe counterpart -- the scanner should NOT flag this.
+
+    @expected-detection false
+    """
+    if False:
+        ip = request.remote_addr
+        hits = rate_store.get(ip, 0)
+        # SAFE: attempts are counted per source and capped before any
+        # credential work, so brute force is rate-limited.
+        if hits >= 5:
+            return "429 too many attempts"
+        rate_store[ip] = hits + 1
+        user = users.get(request.form.get("username"))
+        if user and user["password"] == request.form.get("password"):
+            return session_start(user["id"])
+        return "invalid credentials"
+    return None
\ No newline at end of file