GHSA-J5RM-V3VH-VX94 eduMFA Passkeys: missing expiration flag may allow replay attacks and reuse of old challenges

Impact In eduMFA = 2.9.1 by adding validity information to the userless challenges. Workarounds No known workarounds besides disabling userless login altogether...

CVE-2025-53102 Discourse's WebAuthn challenge isn't cleared from user session after authentication

Discourse is an open-source community discussion platform. Prior to version 3.4.7 on the stable branch and version 3.5.0.beta.8 on the tests-passed branch, upon issuing a physical security key for 2FA, the server generates a WebAuthn challenge, which the client signs. The challenge is not cleared...

DEBIAN-CVE-2002-1336

TightVNC before 1.2.6 generates the same challenge string for multiple connections, which allows remote attackers to bypass VNC authentication by sniffing the challenge and response of other users...

VNC authentication weakness

VNC authentication weakness --------------------------- VNC uses a DES-encrypted challenge-response system to avoid passing passwords over the wire in plaintext. However, it seems that a weakness in the way the challenge is generated by some servers would make this useless. The following program...