CVE-2026-31835 Vaultwarden WebAuthn credential metadata tampered before signature verification

Vaultwarden is a Bitwarden-compatible server written in Rust. In versions 1.35.4 and earlier, the WebAuthn authentication flow in validatewebauthnlogin updates persistent credential metadata 1backupeligible1 and 1backupstate flags1 based on unverified authenticatorData before signature validation...

PT-2026-37215

Name of the Vulnerable Software and Affected Versions Vaultwarden versions prior to 1.35.5 Description The WebAuthn authentication flow in the validate webauthn login function updates persistent credential metadata, specifically the backup eligible and backup state flags, using unverified...