CVE Catalog

CVE-2025-66558

LowCVSS 3.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.28%

19th percentile - higher than 19% of all known CVEs

Summary

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 attacker to take away a 2FA WebAuthn device when correctly guessing an 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 cannot authenticate as the victim.

Risk Assessment

An attacker could remove a victim's 2FA device, weakening account protection and forcing the user to re-register a device, which may be leveraged in further social engineering attacks.

Recommendation

Update the Nextcloud Twofactor WebAuthn app to version 1.4.2 or 2.4.1 (or later).

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS