{"id":"CVE-2026-76216","title":"Vikunja through 2.4.0 contains a principal-type confusion vulnerability where LinkSharing principals with id N are treated as user principals with users.id == N at three permission checks lacking type guards","summary":"Vikunja through 2.4.0 contains a principal-type confusion vulnerability where LinkSharing principals with id N are treated as user principals with users.id == N at three permission checks lacking type guards. Attackers with a link-share …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-639","CWE-843","CWE-863"],"published":"2026-08-19","updated":"2026-09-16","sourceUpdated":"2026-09-16T20:18:30.540","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-76216","references":[{"url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-32r8-5843-4qw2","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/vikunja-through-principal-type-confusion-via-linksharing","label":"disclosure@vulncheck.com"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-76216"},{"url":"https://github.com/advisories/GHSA-32r8-5843-4qw2"},{"url":"https://github.com/go-vikunja/vikunja"},{"url":"https://github.com/go-vikunja/vikunja/commit/a717d64d5658708ba390f18dd697f5e567e68aac"},{"url":"https://github.com/go-vikunja/vikunja/releases/tag/v2.5.0"}],"tags":["nvd","ghsa","go","osv"],"epss":0.00363,"epssPercentile":0.29924,"ingestedAt":"2026-09-16T21:05:36.839Z","aliases":["GHSA-32r8-5843-4qw2","GO-2026-6711"],"ecosystem":"go","vendor":"api","product":"code.vikunja.io/api","affected":["code.vikunja.io/api <= 2.4.0"],"patched":["code.vikunja.io/api 2.5.0"],"slug":"CVE-2026-76216","body":"## Overview\n\nVikunja through 2.4.0 contains a principal-type confusion vulnerability where LinkSharing principals with id N are treated as user principals with users.id == N at three permission checks lacking type guards. Attackers with a link-share JWT can remove victims from teams, enumerate and delete victim bot users, or read team rosters by exploiting id collisions in the autoincrement space.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-76216)\n\nAffected packages:\n\n- `code.vikunja.io/api <= 2.4.0`\n\nSource: https://github.com/advisories/GHSA-32r8-5843-4qw2","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}