security: v1.7.7 hardening release

- Add WEBHOOK_CLIENT_SECRET validation for Graph webhooks
- Add Redis-backed rate limiting (fetch/ask/write/default tiers)
- Validate LLM_BASE_URL to prevent SSRF (HTTPS only, block private IPs)
- Enforce non-wildcard CORS when AUTH_ENABLED=true
- Add Content-Security-Policy headers
- Fix audit middleware to use verified JWT claims via contextvars
- Cap bulk_tags updates to 10,000 documents
- Return generic error messages to clients (no internal detail leakage)
- Strict AlertCondition Pydantic model for alert rules
- Security warning on MCP stdio server startup
- Remove MongoDB/Redis host ports from docker-compose
- Remove mongo_query from /ask API response

.env.example

@@ -64,6 +64,10 @@ ALERT_WEBHOOK_URL=
 ALERT_WEBHOOK_FORMAT=generic  # generic | slack | teams
 ALERT_DEDUPE_MINUTES=15
 
+# Webhook security (optional but strongly recommended)
+# Set this to the same clientState used when creating Graph subscriptions
+WEBHOOK_CLIENT_SECRET=
+
 # Optional: privacy / access control
 # Hide entire services from users without PRIVACY_SERVICE_ROLES
 # PRIVACY_SERVICES=Exchange,Teams

RELEASE_NOTES_v1.7.7.md

@@ -0,0 +1,99 @@
+# AOC v1.7.7 Release Notes
+
+**Release date:** 2026-04-24
+
+---
+
+## Security Hardening
+
+This release is a focused security patch addressing findings from an internal audit. All users running AOC in production are encouraged to upgrade.
+
+### Webhook authentication (`/api/webhooks/graph`)
+- **ClientState validation** — Notifications now require a matching `WEBHOOK_CLIENT_SECRET`. Set this in your `.env` to the same value used when creating Graph subscriptions.
+- Rejects spoofed notification payloads with `401 Unauthorized`.
+
+### Rate limiting
+- **Redis-backed fixed-window rate limiting** is now enabled by default.
+- Per-category limits:
+  - `/api/fetch-audit-logs` — 10 requests/hour
+  - `/api/ask` — 30 requests/minute
+  - `/api/events/bulk-tags` — 20 requests/minute
+  - All other endpoints — 120 requests/minute
+- Returns `429 Too Many Requests` with a `Retry-After` header when exceeded.
+
+### SSRF protection for LLM calls
+- `LLM_BASE_URL` is now validated before every outbound request.
+- Blocks non-HTTPS URLs, localhost, link-local addresses (`169.254.169.254`), and all private IP ranges.
+
+### CORS enforcement
+- Wildcard (`*`) origins are **automatically stripped** when `AUTH_ENABLED=true`.
+- A startup warning is logged if an insecure CORS configuration is detected.
+
+### Content Security Policy
+- API and HTML responses now include a `Content-Security-Policy` header.
+- Restricts script sources to self, CDN origins, and MSAL auth library.
+
+### Audit trail integrity
+- The audit middleware no longer parses JWT tokens without signature verification.
+- Verified claims are now propagated safely via `contextvars`, eliminating audit log poisoning.
+
+### Standalone MCP server
+- Prints a prominent security warning on startup reminding operators that the stdio transport has no authentication layer.
+
+---
+
+## Operational Improvements
+
+### Bulk tag cap
+- `POST /api/events/bulk-tags` now refuses to update more than **10,000 events** in a single request.
+- Returns `400` with guidance to narrow filters.
+
+### Generic error responses
+- Internal exception details are no longer leaked in HTTP 500/502 responses.
+- Full stack traces remain in server-side logs.
+
+### Alert rule schema
+- `conditions` field now uses a strict Pydantic model (`AlertCondition`) instead of an unconstrained `list[dict]`.
+- Prevents stored data pollution from malformed rule payloads.
+
+### Docker Compose
+- MongoDB (`27017`) and Redis (`6379`) ports are no longer forwarded to the Docker host.
+- Internal services are reachable only via the Docker network.
+
+---
+
+## Configuration
+
+Add to your `.env`:
+
+```bash
+# Required if you use Graph webhooks
+WEBHOOK_CLIENT_SECRET=your-random-secret
+
+# Optional: disable rate limiting (not recommended)
+RATE_LIMIT_ENABLED=true
+RATE_LIMIT_REQUESTS=120
+RATE_LIMIT_WINDOW_SECONDS=60
+```
+
+---
+
+## Upgrade notes
+
+**No breaking changes.** Existing event data, tags, comments, and saved searches are preserved.
+
+After pulling:
+
+```bash
+export AOC_VERSION=v1.7.7
+docker compose -f docker-compose.prod.yml pull
+docker compose -f docker-compose.prod.yml up -d
+```
+
+---
+
+## Docker image
+
+```
+git.cqre.net/cqrenet/aoc-backend:v1.7.7
+```

VERSION

@@ -1 +1 @@
-1.7.6
+1.7.7

backend/auth.py

@@ -1,3 +1,4 @@
+import contextvars
 import time
 
 import requests
@@ -15,6 +16,9 @@ from fastapi import Header, HTTPException
 from jwt import ExpiredSignatureError, InvalidTokenError, decode
 from jwt.algorithms import RSAAlgorithm
 
+# Thread-/task-local storage for verified auth claims (used by audit middleware)
+_auth_context: contextvars.ContextVar[dict | None] = contextvars.ContextVar("auth_context", default=None)
+
 JWKS_CACHE = {"exp": 0, "keys": []}
 logger = structlog.get_logger("aoc.auth")
 
@@ -94,7 +98,9 @@ def user_can_access_privacy_services(claims: dict) -> bool:
 
 def require_auth(authorization: str | None = Header(None)):
     if not AUTH_ENABLED:
-        return {"sub": "anonymous"}
+        user = {"sub": "anonymous"}
+        _auth_context.set(user)
+        return user
 
     if not authorization or not authorization.lower().startswith("bearer "):
         raise HTTPException(status_code=401, detail="Missing bearer token")
@@ -106,4 +112,5 @@ def require_auth(authorization: str | None = Header(None)):
     if not _allowed(claims, AUTH_ALLOWED_ROLES, AUTH_ALLOWED_GROUPS):
         raise HTTPException(status_code=403, detail="Forbidden")
 
+    _auth_context.set(claims)
     return claims

backend/config.py

@@ -68,6 +68,14 @@ class Settings(BaseSettings):
     ALERT_WEBHOOK_FORMAT: str = "generic"  # generic | slack | teams
     ALERT_DEDUPE_MINUTES: int = 15
 
+    # Webhook security
+    WEBHOOK_CLIENT_SECRET: str = ""
+
+    # Rate limiting
+    RATE_LIMIT_ENABLED: bool = True
+    RATE_LIMIT_REQUESTS: int = 120
+    RATE_LIMIT_WINDOW_SECONDS: int = 60
+
 
 _settings = Settings()
 
@@ -113,3 +121,9 @@ DEFAULT_PAGE_SIZE = _settings.DEFAULT_PAGE_SIZE
 ALERT_WEBHOOK_URL = _settings.ALERT_WEBHOOK_URL
 ALERT_WEBHOOK_FORMAT = _settings.ALERT_WEBHOOK_FORMAT
 ALERT_DEDUPE_MINUTES = _settings.ALERT_DEDUPE_MINUTES
+
+WEBHOOK_CLIENT_SECRET = _settings.WEBHOOK_CLIENT_SECRET
+
+RATE_LIMIT_ENABLED = _settings.RATE_LIMIT_ENABLED
+RATE_LIMIT_REQUESTS = _settings.RATE_LIMIT_REQUESTS
+RATE_LIMIT_WINDOW_SECONDS = _settings.RATE_LIMIT_WINDOW_SECONDS

backend/main.py

@@ -6,7 +6,7 @@ from pathlib import Path
 
 import structlog
 from audit_trail import log_action
-from config import AI_FEATURES_ENABLED, CORS_ORIGINS, ENABLE_PERIODIC_FETCH, FETCH_INTERVAL_MINUTES
+from config import AI_FEATURES_ENABLED, AUTH_ENABLED, CORS_ORIGINS, ENABLE_PERIODIC_FETCH, FETCH_INTERVAL_MINUTES
 from database import setup_indexes
 from fastapi import FastAPI, HTTPException, Request
 from fastapi.middleware.cors import CORSMiddleware
@@ -52,10 +52,19 @@ logger = structlog.get_logger("aoc.fetcher")
 
 app = FastAPI()
 
+# CORS: reject wildcard in production when auth is enabled
+_effective_cors = CORS_ORIGINS
+if AUTH_ENABLED and "*" in _effective_cors:
+    logger.warning(
+        "CORS wildcard (*) is insecure when AUTH_ENABLED=true. "
+        "Removing wildcard. Set CORS_ORIGINS explicitly in production."
+    )
+    _effective_cors = [o for o in _effective_cors if o != "*"] or ["http://localhost:8000"]
+
 app.add_middleware(CorrelationIdMiddleware)
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=CORS_ORIGINS,
+    allow_origins=_effective_cors,
     allow_credentials=True,
     allow_methods=["*"],
     allow_headers=["*"],
@@ -80,27 +89,39 @@ async def cache_control_middleware(request: Request, call_next):
         response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
         response.headers["Pragma"] = "no-cache"
         response.headers["Expires"] = "0"
+    # Basic CSP for the UI and API
+    if request.url.path.startswith("/api/") or request.url.path in ("/", "/index.html"):
+        response.headers["Content-Security-Policy"] = (
+            "default-src 'self'; "
+            "script-src 'self' 'unsafe-inline' cdn.jsdelivr.net alcdn.msauth.net; "
+            "style-src 'self' 'unsafe-inline'; "
+            "connect-src 'self'; "
+            "img-src 'self' data:;"
+        )
     return response
 
 
+@app.middleware("http")
+async def rate_limit_middleware(request: Request, call_next):
+    """Apply Redis-backed rate limiting before processing the request."""
+    if request.url.path.startswith("/api/"):
+        from rate_limiter import check_rate_limit
+
+        await check_rate_limit(request)
+    return await call_next(request)
+
+
 @app.middleware("http")
 async def audit_middleware(request: Request, call_next):
     response = await call_next(request)
     if request.url.path.startswith("/api/") and request.method in ("POST", "PATCH", "PUT", "DELETE"):
-        from auth import AUTH_ENABLED
-
         user = "anonymous"
         if AUTH_ENABLED:
-            auth_header = request.headers.get("authorization", "")
-            if auth_header.lower().startswith("bearer "):
-                try:
-                    from jose import jwt
+            from auth import _auth_context
 
-                    token = auth_header.split(" ", 1)[1]
-                    claims = jwt.get_unverified_claims(token)
-                    user = claims.get("sub", "unknown")
-                except Exception:
-                    pass
+            claims = _auth_context.get(None)
+            if isinstance(claims, dict):
+                user = claims.get("sub", "unknown")
         log_action(
             action=request.method.lower(),
             resource=request.url.path,
@@ -152,6 +173,19 @@ async def version():
     return {"version": os.environ.get("VERSION", "unknown")}
 
 
+@app.exception_handler(Exception)
+async def generic_exception_handler(request: Request, exc: Exception):
+    """Return generic error messages for unhandled exceptions to avoid info leakage."""
+    if isinstance(exc, HTTPException):
+        raise exc
+    logger.error("Unhandled exception", path=request.url.path, error=str(exc))
+    return Response(
+        content='{"detail":"Internal server error"}',
+        status_code=500,
+        media_type="application/json",
+    )
+
+
 frontend_dir = Path(__file__).parent / "frontend"
 app.mount("/", StaticFiles(directory=frontend_dir, html=True), name="frontend")
 

backend/mcp_server.py

@@ -41,6 +41,15 @@ from mcp_common import (
     handle_search_events,
 )
 
+# Security warning: this standalone stdio server has no authentication.
+# Only run it in trusted environments (e.g. local Claude Desktop) and
+# ensure the MongoDB connection uses authenticated credentials.
+print("=" * 60, file=sys.stderr)
+print("AOC MCP Server (stdio transport)", file=sys.stderr)
+print("WARNING: No authentication layer. Only run in trusted", file=sys.stderr)
+print("environments or behind a VPN. See AGENTS.md for details.", file=sys.stderr)
+print("=" * 60, file=sys.stderr)
+
 app = Server("aoc")
 
 

backend/models/api.py

@@ -63,12 +63,18 @@ class CommentAddRequest(BaseModel):
     text: str
 
 
+class AlertCondition(BaseModel):
+    field: str
+    op: str  # eq, neq, contains, in, after_hours
+    value: str | list[str] | None = None
+
+
 class AlertRuleResponse(BaseModel):
     id: str | None = None
     name: str
     enabled: bool
     severity: str
-    conditions: list[dict]
+    conditions: list[AlertCondition]
     message: str
 
 

backend/rate_limiter.py

@@ -0,0 +1,82 @@
+"""Simple Redis-backed fixed-window rate limiter."""
+
+import time
+
+import structlog
+from config import RATE_LIMIT_ENABLED, RATE_LIMIT_REQUESTS, RATE_LIMIT_WINDOW_SECONDS
+from fastapi import HTTPException, Request
+from redis_client import get_redis
+
+logger = structlog.get_logger("aoc.rate_limit")
+
+
+class RateLimitExceeded(HTTPException):
+    def __init__(self, retry_after: int):
+        super().__init__(
+            status_code=429,
+            detail="Rate limit exceeded. Please slow down.",
+            headers={"Retry-After": str(retry_after)},
+        )
+
+
+def _get_identifier(request: Request) -> str:
+    """Best-effort client identifier: authenticated sub, or X-Forwarded-For, or client host."""
+    user = getattr(request.state, "user", None)
+    if user and isinstance(user, dict):
+        sub = user.get("sub")
+        if sub and sub != "anonymous":
+            return f"user:{sub}"
+
+    forwarded = request.headers.get("x-forwarded-for")
+    if forwarded:
+        return f"ip:{forwarded.split(',')[0].strip()}"
+
+    return f"ip:{request.client.host if request.client else 'unknown'}"
+
+
+def _get_path_category(path: str) -> str:
+    """Bucket paths into rate-limit categories."""
+    if path.startswith("/api/fetch"):
+        return "fetch"
+    if path.startswith("/api/ask"):
+        return "ask"
+    if path.startswith("/api/events/bulk-tags"):
+        return "write"
+    return "default"
+
+
+def _limit_for_category(category: str) -> tuple[int, int]:
+    """Return (max_requests, window_seconds) for a category."""
+    if category == "fetch":
+        return (10, 3600)  # 10 per hour
+    if category == "ask":
+        return (30, 60)  # 30 per minute
+    if category == "write":
+        return (20, 60)  # 20 per minute
+    return (RATE_LIMIT_REQUESTS, RATE_LIMIT_WINDOW_SECONDS)
+
+
+async def check_rate_limit(request: Request):
+    """Raise RateLimitExceeded if the client has exceeded their quota."""
+    if not RATE_LIMIT_ENABLED:
+        return
+
+    category = _get_path_category(request.url.path)
+    limit, window = _limit_for_category(category)
+
+    identifier = _get_identifier(request)
+    now = int(time.time())
+    window_key = now // window
+    redis_key = f"rate_limit:{identifier}:{category}:{window_key}"
+
+    try:
+        redis = await get_redis()
+        count = await redis.incr(redis_key)
+        if count == 1:
+            await redis.expire(redis_key, window)
+        if count > limit:
+            raise RateLimitExceeded(retry_after=window - (now % window))
+    except RateLimitExceeded:
+        raise
+    except Exception as exc:
+        logger.warning("Rate limiter Redis error; allowing request", error=str(exc))

backend/routes/ask.py

@@ -397,8 +397,31 @@ def _format_events_for_llm(
     return "\n".join(lines)
 
 
+def _validate_llm_url(url: str):
+    """Prevent SSRF by rejecting internal/reserved addresses."""
+    from urllib.parse import urlparse
+
+    parsed = urlparse(url)
+    if parsed.scheme != "https":
+        raise RuntimeError("LLM_BASE_URL must use HTTPS")
+    hostname = (parsed.hostname or "").lower()
+    if not hostname:
+        raise RuntimeError("LLM_BASE_URL must have a valid hostname")
+    blocked = {"localhost", "127.0.0.1", "0.0.0.0", "::1", "169.254.169.254"}
+    if hostname in blocked:
+        raise RuntimeError(f"LLM_BASE_URL hostname '{hostname}' is not allowed")
+    # Block link-local and private IP ranges
+    import ipaddress
+
+    try:
+        ip = ipaddress.ip_address(hostname)
+        if ip.is_private or ip.is_loopback or ip.is_link_local or ip.is_reserved:
+            raise RuntimeError(f"LLM_BASE_URL IP '{hostname}' is not allowed")
+    except ValueError:
+        pass  # hostname is not an IP, which is fine
+
+
 def _build_chat_url(base_url: str, api_version: str) -> str:
-    """Construct the chat completions URL, handling Azure OpenAI endpoints."""
     base = base_url.rstrip("/")
     url = base if base.endswith("/chat/completions") else f"{base}/chat/completions"
     if api_version:
@@ -424,6 +447,9 @@ async def _call_llm(
         },
     ]
 
+    # SSRF guard: only allow known public HTTPS endpoints
+    _validate_llm_url(LLM_BASE_URL)
+
     url = _build_chat_url(LLM_BASE_URL, LLM_API_VERSION)
     headers = {
         "Content-Type": "application/json",
@@ -570,6 +596,8 @@ async def _explain_event(event: dict, related: list[dict]) -> str:
         },
     ]
 
+    _validate_llm_url(LLM_BASE_URL)
+
     url = _build_chat_url(LLM_BASE_URL, LLM_API_VERSION)
     headers = {"Content-Type": "application/json"}
     if "azure" in LLM_BASE_URL.lower() or "cognitiveservices" in LLM_BASE_URL.lower():
@@ -731,7 +759,7 @@ async def ask_question(body: AskRequest, user: dict = Depends(require_auth)):
         raw_events = list(cursor)
     except Exception as exc:
         logger.error("Failed to query events for ask", error=str(exc))
-        raise HTTPException(status_code=500, detail=f"Database query failed: {exc}") from exc
+        raise HTTPException(status_code=500, detail="Database query failed") from exc
 
     for e in raw_events:
         e["_id"] = str(e.get("_id", ""))
@@ -803,7 +831,6 @@ async def ask_question(body: AskRequest, user: dict = Depends(require_auth)):
                     "total_matched": total,
                     "services_queried": query_services,
                     "excluded_services": excluded_services,
-                    "mongo_query": json.dumps(query, default=str),
                 },
                 llm_used=False,
                 llm_error=None,
@@ -863,7 +890,6 @@ async def ask_question(body: AskRequest, user: dict = Depends(require_auth)):
             "total_matched": total,
             "services_queried": query_services,
             "excluded_services": excluded_services,
-            "mongo_query": json.dumps(query, default=str),
         },
         llm_used=llm_used,
         llm_error=llm_error,

backend/routes/events.py

@@ -158,7 +158,7 @@ def list_events(
         cursor_query = events_collection.find(query).sort([("timestamp", -1), ("_id", -1)]).limit(safe_page_size)
         events = list(cursor_query)
     except Exception as exc:
-        raise HTTPException(status_code=500, detail=f"Failed to query events: {exc}") from exc
+        raise HTTPException(status_code=500, detail="Failed to query events") from exc
 
     next_cursor = None
     if len(events) == safe_page_size:
@@ -241,9 +241,17 @@ def bulk_tags(
     update = {"$set": {"tags": tags}} if body.mode == "replace" else {"$addToSet": {"tags": {"$each": tags}}}
 
     try:
+        matched = events_collection.count_documents(query, limit=10001)
+        if matched > 10000:
+            raise HTTPException(
+                status_code=400,
+                detail="Bulk tag update matches too many events (>10000). Narrow your filters.",
+            )
         result_obj = events_collection.update_many(query, update)
+    except HTTPException:
+        raise
     except Exception as exc:
-        raise HTTPException(status_code=500, detail=f"Failed to update tags: {exc}") from exc
+        raise HTTPException(status_code=500, detail="Failed to update tags") from exc
 
     log_action(
         "bulk_tags",
@@ -268,7 +276,7 @@ def filter_options(
         actor_upns = sorted([a for a in events_collection.distinct("actor_upn") if a])[:safe_limit]
         devices = sorted([a for a in events_collection.distinct("target_displays") if isinstance(a, str)])[:safe_limit]
     except Exception as exc:
-        raise HTTPException(status_code=500, detail=f"Failed to load filter options: {exc}") from exc
+        raise HTTPException(status_code=500, detail="Failed to load filter options") from exc
 
     if not user_can_access_privacy_services(user):
         services = [s for s in services if s not in PRIVACY_SERVICES]

backend/routes/fetch.py

@@ -1,5 +1,6 @@
 import time
 
+import structlog
 from audit_trail import log_action
 from auth import require_auth
 from config import ALERTS_ENABLED
@@ -15,6 +16,8 @@ from sources.intune_audit import fetch_intune_audit
 from sources.unified_audit import fetch_unified_audit
 from watermark import get_watermark, set_watermark
 
+logger = structlog.get_logger("aoc.fetch")
+
 router = APIRouter(dependencies=[Depends(require_auth)])
 
 
@@ -85,5 +88,8 @@ def fetch_logs(
             user.get("sub", "anonymous"),
         )
         return result
+    except HTTPException:
+        raise
     except Exception as exc:
-        raise HTTPException(status_code=502, detail=str(exc)) from exc
+        logger.error("Fetch failed", error=str(exc))
+        raise HTTPException(status_code=502, detail="Failed to fetch audit logs") from exc

backend/routes/webhooks.py

@@ -1,4 +1,5 @@
 import structlog
+from config import WEBHOOK_CLIENT_SECRET
 from fastapi import APIRouter, Request, Response
 
 router = APIRouter()
@@ -10,9 +11,12 @@ async def graph_webhook(request: Request):
     """
     Receive Microsoft Graph change notifications.
     Handles the validation handshake by echoing validationToken.
+    Validates clientState on notifications to prevent spoofing.
     """
     validation_token = request.query_params.get("validationToken")
     if validation_token:
+        # Microsoft sends validationToken as a query param during subscription creation.
+        # Echo it back as plain text to prove endpoint ownership.
         return Response(content=validation_token, media_type="text/plain")
 
     try:
@@ -21,12 +25,26 @@ async def graph_webhook(request: Request):
         logger.warning("Invalid webhook payload", error=str(exc))
         return Response(status_code=400)
 
-    for notification in body.get("value", []):
+    notifications = body.get("value", [])
+    if not isinstance(notifications, list):
+        logger.warning("Invalid webhook payload structure")
+        return Response(status_code=400)
+
+    for notification in notifications:
+        client_state = notification.get("clientState")
+        if WEBHOOK_CLIENT_SECRET and client_state != WEBHOOK_CLIENT_SECRET:
+            logger.warning(
+                "Graph webhook rejected: invalid clientState",
+                change_type=notification.get("changeType"),
+                resource=notification.get("resource"),
+            )
+            return Response(status_code=401)
+
         logger.info(
             "Received Graph notification",
             change_type=notification.get("changeType"),
             resource=notification.get("resource"),
-            client_state=notification.get("clientState"),
+            client_state=client_state,
         )
 
     return {"status": "accepted"}

docker-compose.yml

@@ -3,8 +3,7 @@ services:
     image: valkey/valkey:8-alpine
     container_name: aoc-redis
     restart: always
-    ports:
-      - "6379:6379"
+    # Ports not exposed to host; backend and worker connect via Docker network
     volumes:
       - redis_data:/data
 
@@ -12,8 +11,7 @@ services:
     image: mongo:7
     container_name: aoc-mongo
     restart: always
-    ports:
-      - "27017:27017"
+    # Ports not exposed to host; backend and worker connect via Docker network
     environment:
       MONGO_INITDB_ROOT_USERNAME: ${MONGO_ROOT_USERNAME}
       MONGO_INITDB_ROOT_PASSWORD: ${MONGO_ROOT_PASSWORD}