{"id":"CVE-2026-55064","title":"Vikunja is an open-source self-hosted task management platform","summary":"Vikunja is an open-source self-hosted task management platform. From 2.3.0 until 2.4.0, a user with Write but not Admin permission on a shared child project can detach it from its parent hierarchy by submitting parent_project_id equal to…","severity":"medium","cvss":4.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","cwe":["CWE-862"],"vendor":"api","product":"code.vikunja.io/api","affected":["code.vikunja.io/api >= 2.3.0, < 2.4.0"],"patched":["code.vikunja.io/api 2.4.0"],"published":"2026-08-28","updated":"2026-09-09","sourceUpdated":"2026-09-09T21:09:13.080","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-55064","references":[{"url":"https://github.com/go-vikunja/vikunja/commit/781ffac198548ae4f3d1febc613caed8e0e11d01","label":"security-advisories@github.com"},{"url":"https://github.com/go-vikunja/vikunja/pull/3239","label":"security-advisories@github.com"},{"url":"https://github.com/go-vikunja/vikunja/releases/tag/v2.4.0","label":"security-advisories@github.com"},{"url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-44v6-7fxq-vgf4","label":"security-advisories@github.com"},{"url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-44v6-7fxq-vgf4","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://github.com/advisories/GHSA-44v6-7fxq-vgf4"}],"tags":["nvd","ghsa","go"],"epss":0.00268,"epssPercentile":0.1918,"aliases":["GHSA-44v6-7fxq-vgf4"],"ecosystem":"go","ingestedAt":"2026-08-28T17:22:56.524Z","slug":"CVE-2026-55064","body":"## Overview\n\nVikunja is an open-source self-hosted task management platform. From 2.3.0 until 2.4.0, a user with Write but not Admin permission on a shared child project can detach it from its parent hierarchy by submitting parent_project_id equal to 0 to POST /api/v1/projects/{project}. The Project.CanUpdate authorization check in pkg/models/project_permissions.go and UpdateProject logic in pkg/models/project.go only gate nonzero parent values, while UpdateProject always persists parent_project_id, so the explicit zero value bypasses the Admin requirement introduced for CVE-2026-35595. Detachment severs the recursive permission-inheritance chain and can disrupt the owner’s hierarchy and inherited collaborator access. This issue is fixed in version 2.4.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-55064)\n\nAffected packages:\n\n- `code.vikunja.io/api >= 2.3.0, < 2.4.0`\n\nPatched in:\n\n- `code.vikunja.io/api 2.4.0`\n\nSource: https://github.com/advisories/GHSA-44v6-7fxq-vgf4","depth":"sunlit","depthScore":24,"depthScoreParts":{"impact":23.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}