CVE-2026-68581 (GCVE-0-2026-68581)

Vulnerability from cvelistv5 – Published: 2026-08-02 12:15 – Updated: 2026-08-03 15:02
VLAI
Title
Vikunja 0.22.0 through 2.3.0 Authentication Bypass via Principal ID Collision
Summary
Vikunja versions 0.22.0 through 2.3.0 fail to validate the principal type in API token management. Because user IDs and link-share IDs are independent numeric sequences and both resolve through a generic web.Auth.GetID() interface, a link-share JWT whose numeric ID equals a target user's ID is treated as that user by the /api/v1/tokens endpoints. An authenticated attacker can obtain a target's numeric user ID via authenticated user search, then create link shares on an attacker-writable project until the link-share sequence reaches that value, and use the resulting link-share JWT to list, create, and delete the target user's API tokens (including issuing a new token with attacker-chosen scopes under the target's permissions). Fixed in version 2.4.0.
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-863 - Incorrect Authorization
Assigner
Impacted products
Vendor Product Version
go-vikunja vikunja Affected: 0.22.0 , < 2.4.0 (semver)
Create a notification for this product.
Date Public
2026-07-19 00:00
Credits
ryuyunseong
Show details on NVD website

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