{"id":"CVE-2026-68581","title":"Vikunja versions 0.22.0 through 2.3.0 fail to validate the principal type in API token management","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 lin…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-863"],"published":"2026-08-02","updated":"2026-09-08","sourceUpdated":"2026-09-08T20:34:34.997","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-68581","references":[{"url":"https://github.com/go-vikunja/vikunja/commit/95b7e673fb5ee407498fa4b13e8b4c57847a4a0b","label":"disclosure@vulncheck.com"},{"url":"https://github.com/go-vikunja/vikunja/commit/e6b25bd57b537ef9a72b5acdadf446ca5ef77bfa","label":"disclosure@vulncheck.com"},{"url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vvcv-vpph-h844","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/vikunja-through-authentication-bypass-via-principal-id-collision","label":"disclosure@vulncheck.com"},{"url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vvcv-vpph-h844","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00422,"epssPercentile":0.36062,"ingestedAt":"2026-08-02T13:18:30.091Z","slug":"CVE-2026-68581","body":"## Overview\n\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## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}