CVE-2025-66558
December 05, 2025
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.
Affected Packages
https://github.com/nextcloud/twofactor_webauthn.git (SCM_GIT):
Affected version(s) >=v0.3.1 <v1.4.2Fix Suggestion:
Update to version v1.4.2https://github.com/nextcloud/twofactor_webauthn.git (SCM_GIT):
Affected version(s) >=v0.3.1 <v1.4.2Fix Suggestion:
Update to version v1.4.2https://github.com/nextcloud/twofactor_webauthn.git (SCM_GIT):
Affected version(s) =v2.4.0 <v2.4.1Fix Suggestion:
Update to version v2.4.1https://github.com/nextcloud/twofactor_webauthn.git (SCM_GIT):
Affected version(s) =v2.4.0 <v2.4.1Fix Suggestion:
Update to version v2.4.1Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
2.3
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
3.1
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Authorization Bypass Through User-Controlled Key
EPSS
Base Score:
0.02
