Coturn is a free open source implementation of TURN and STUN Server. Versions prior to 4.11.0 contain a stored cross-site scripting (XSS) vulnerability in the web-admin HTTPS interface. An attacker who can create a TURN allocation with a crafted USERNAME value can inject HTML/JavaScript that executes when an authenticated web-admin user views the TURN session list. In configurations using anonymous TURN access (--no-auth), this may be exploitable without TURN credentials. In authenticated deployments, exploitation requires valid TURN credentials or control over a provisioned username. This issue has been fixed in version 4.11.0.

Coturn is a free open source implementation of TURN and STUN Server. Versions prior to 4.10.0 contain a stack buffer overflow in decode_oauth_token_gcm(). A uint16_t nonce_len field read from an attacker-supplied OAuth access token (0-65535) is passed directly to memcpy() as the copy length into a 256-byte stack buffer (oauth_encrypted_block.nonce[256]) without bounds checking. The overflow occurs before AES-GCM authentication is verified, the attacker does not need to know the OAuth key or produce a valid AES-GCM token. Up to 735 bytes of attacker-controlled data are written past the buffer, may corrupt adjacent stack data, including control-flow data depending on compiler, ABI, and mitigations. Requires --oauth mode (non-default). This may provide a plausible RCE primitive depending on exploit mitigations; because coturn is widely deployed for WebRTC TURN/STUN and --oauth is commonly recommended, impact can be broad. This issue has been fixed in version 4.10.0.