Low 3.1Published Dec 5, 2025

CVE-2025-66558Nextcloud Twofactor WebAuthn app was updated based on public key

Updated under an hour ago (Oct 26, 2026, 3:00 PM ET)

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It affects nextcloud security-advisories and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for nextcloud security-advisories

Exploited in the last 30 days

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.

CVSS: 3.1 LOW (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
Weakness (CWE): CWE-639
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Dec 5, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

nextcloud security-advisories nextcloud:security_advisories (from the name)	before 1.4.2; from 2.0.0-beta.1, < 2.4.1	CNA record
nextcloud two-factor_webauthn nextcloud:two-factor_webauthn	from 1.0.0 before 1.4.2; from 2.0.0 before 2.4.1	NVD

References

References

https://github.com/nextcloud/security-advisories/security/advisories/GHSA-fr8x-mvjg-wf9q	x-refsource-confirm, patch, vendor-advisory
https://github.com/nextcloud/twofactor_webauthn/pull/881	x-refsource-misc, issue-tracking, patch
https://github.com/nextcloud/twofactor_webauthn/commit/5d2302166d31ee2e01b2e21556bd5372156da13d	x-refsource-misc, patch
https://hackerone.com/reports/3360354	x-refsource-misc, permissions-required, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.