In github.com/pion/webrtc, failed DTLS certificate verification doesn't stop data channel communication

Impact

Data channel communication was incorrectly allowed with users who have failed DTLS certificate verification.

This attack requires

• Attacker knows the ICE password.
• Only take place during PeerConnection handshake.

This attack can be detected by monitoring PeerConnectionState in all versions of Pion WebRTC.

Patches

Users should upgrade to v3.0.15.

The exact patch is https://github.com/pion/webrtc/commit/545613dcdeb5dedb01cce94175f40bcbe045df2e

Workarounds

Users should listen for when PeerConnectionState changes to PeerConnectionStateFailed. When it enters this state users should not continue using the PeerConnection.

For more information

If you have any questions or comments about this advisory:

• Open an issue in https://github.com/pion/webrtc
• Email us at [email protected]

Thank you to https://github.com/Gaukas for discovering this.