CVE-2026-35597

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 v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/commit/6ca0151d02fa0e8c7e2181ab916a28e08caaaec8	Patch
https://github.com/go-vikunja/vikunja/pull/2576	Issue Tracking
https://github.com/go-vikunja/vikunja/releases/tag/v2.3.0	Release Notes
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-fgfv-pv97-6cmj	Exploit Vendor Advisory
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-fgfv-pv97-6cmj	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-10 17:17

Updated : 2026-06-17 10:40

NVD link : CVE-2026-35597

Mitre link : CVE-2026-35597

CVE.ORG link : CVE-2026-35597

JSON object : View

Products Affected

vikunja

vikunja

CWE

CWE-307

Improper Restriction of Excessive Authentication Attempts

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