{"id":"GHSA-9jrx-vmh8-c6xw","title":"Duplicate Advisory: Vikunja: Link-share principal ID collision allows cross-account API token issuance and management","summary":"Duplicate Advisory: Vikunja: Link-share principal ID collision allows cross-account API token issuance and management","severity":"high","cvss":8.1,"cwe":["CWE-863"],"vendor":"api","product":"code.vikunja.io/api","ecosystem":"go","affected":["code.vikunja.io/api >= 0.22.0, <= 2.3.0"],"published":"2026-08-02","updated":"2026-10-09","sourceUpdated":"2026-10-09T20:42:08Z","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-9jrx-vmh8-c6xw","references":[{"url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vvcv-vpph-h844"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68581"},{"url":"https://github.com/go-vikunja/vikunja/commit/95b7e673fb5ee407498fa4b13e8b4c57847a4a0b"},{"url":"https://github.com/go-vikunja/vikunja/commit/e6b25bd57b537ef9a72b5acdadf446ca5ef77bfa"},{"url":"https://www.vulncheck.com/advisories/vikunja-through-authentication-bypass-via-principal-id-collision"},{"url":"https://github.com/advisories/GHSA-9jrx-vmh8-c6xw"}],"tags":["ghsa","go"],"ingestedAt":"2026-10-09T21:12:42.335Z","slug":"GHSA-9jrx-vmh8-c6xw","body":"## Overview\n\n### Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-vvcv-vpph-h844. This link is maintained to preserve external references.\n\n### Original Description\nVikunja 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.\n\n## Affected packages\n\n- `code.vikunja.io/api >= 0.22.0, <= 2.3.0`\n\n## Remediation\n\nRefer to the advisory for the patched release.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}