CVE-2025-66558 — Nextcloud Twofactor WebAuthn app was updated based on public key
Nextcloud Twofactor WebAuthn is the WebAuthn Two-Factor Provider for Nextcloud. Prior to 1.4.2 and 2.4.1, a missing ownership check allowed an attack to take-away a 2FA webauthn…
Published: 2025-12-05 · CVSS: 3.1 · CVSS 3.1
Nextcloud Twofactor WebAuthn is the WebAuthn Two-Factor Provider for Nextcloud. Prior to 1.4.2 and 2.4.1, a missing ownership check allowed an attack to take-away a 2FA webauthn device when correctly guessing a 80-128 character long random string of letters, numbers and symbols. The victim would then be prompted to register a new device on the next login. The attacker can not authenticate as the victim. This vulnerability is fixed in 1.4.2 and 2.4.1.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7