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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-66558 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-fr8x-mvjg-wf9q GitHub, Inc.
https://github.com/nextcloud/twofactor_webauthn/commit/5d2302166d31ee2e01b2e21556bd5372156da13d GitHub, Inc.
https://github.com/nextcloud/twofactor_webauthn/pull/881 GitHub, Inc.
https://hackerone.com/reports/3360354 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-639 Authorization Bypass Through User-Controlled Key GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-66558
NVD Published Date:
12/05/2025
NVD Last Modified:
12/05/2025
Source:
GitHub, Inc.