CVE-2026-35597
The in-memory counter correctly increments past 10, so the lockout code executes on every subsequent attempt, but the database write is rolled back every time.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, the TOTP failed-attempt lockout mechanism is non-functional due to a database transaction handling bug. When a TOTP validation fails, the login handler in pkg/routes/api/v1/login.go calls HandleFailedTOTPAuth and then unconditionally rolls back. HandleFailedTOTPAuth in pkg/user/totp.go uses an in-memory counter (key-value store) to track failed attempts. When the counter reaches 10, it calls user.SetStatus(s, StatusAccountLocked) on the same database session s. Because the login handler always rolls back after a TOTP failure, the StatusAccountLocked write is undone. The in-memory counter correctly increments past 10, so the lockout code executes on every subsequent attempt, but the database write is rolled back every time. This allows unlimited brute-force attempts against TOTP codes. This vulnerability is fixed in 2.3.0.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.30% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-307
- Affected
- vikunja/vikunja
- Source
- security-advisories@github.com
References
- https://github.com/go-vikunja/vikunja/commit/6ca0151d02fa0e8c7e2181ab916a28e08caaaec8Patch
- https://github.com/go-vikunja/vikunja/pull/2576Issue Tracking
- https://github.com/go-vikunja/vikunja/releases/tag/v2.3.0Release Notes
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-fgfv-pv97-6cmjExploit, Vendor Advisory
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-fgfv-pv97-6cmjExploit, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.