CVE-2026-35597 MEDIUM

CVE-2026-35597: Vikunja Affected by TOTP Brute-Force Due to Non-Functional Account Lockout

Vendor Go-Vikunja
Product vikunja
Weakness CWE-307 · Brute force
Published April 10, 2026
Last update April 13, 2026

CVSS base score

5.9/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 10, 2026 CVE published
April 13, 2026 Record updated