Description
Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, an authentication bypass vulnerability allowed attackers with knowledge of a user's password to circumvent two-factor authentication (2FA) protections. When a user initiated login with valid credentials on a 2FA-enabled account, the system created a temporary session token before enforcing the second factor challenge. This token could be extracted and replayed via HTTP Basic Authentication to gain unauthorized access to authenticated endpoints. It is recommended that the Nextcloud Server is upgraded to 33.0.3 or 32.0.9. It is recommended that the Nextcloud Enterprise Server is upgraded to 33.0.3, 32.0.9, 31.0.14.5, 30.0.17.9 or 29.0.16.16
Affected products
nextcloud: nextcloud server
References3
- github.com/nextcloud/security-advisories/security/advisories/GH… Vendor Advisory
- github.com/nextcloud/server/pull/59758 Issue TrackingPatch
- hackerone.com/reports/3639301 Permissions Required
Metrics
- CVSS 3.1
-
5.9
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N - EPSS — exploit probability
- 0% percentile: 22 · as of 15 November 2026
- CWE
- CWE-287
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