CVE-2025-66558

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

05/12/2025

Last modified:

09/12/2025

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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 3.10 LOW
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): Low
Availability (A): None

Base Score 3.x

3.10

Severity 3.x

LOW

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:nextcloud:two-factor_webauthn::::::::	1.0.0 (including)	1.4.2 (excluding)
cpe:2.3:a:nextcloud:two-factor_webauthn::::::::	2.0.0 (including)	2.4.1 (excluding)

To consult the complete list of CPE names with products and versions, see this page

CVE-2025-66558

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools