{"id":"CVE-2026-55066","summary":"Vikunja: Cross-tenant IDOR in kanban move-task endpoint via unauthorized body task_id","details":"Vikunja is an open-source self-hosted task management platform. Prior to 2.4.0, POST /api/v1/projects/{project}/views/{view}/buckets/{bucket}/tasks accepts a body supplied task_id but TaskBucket.CanUpdate in pkg/models/kanban_task_bucket.go authorizes only the project, view, and bucket from the URL. updateTaskBucket then calls Task.ReadOne without a separate task permission check, returns the victim task contents, and can update the task done state when the attacker chooses a done bucket. Because task identifiers are global sequential values, an authenticated user can enumerate cross-tenant tasks and modify their completion metadata through both the v1 and v2 routes that share this model. This issue is fixed in version 2.4.0.","aliases":["GHSA-5pg6-m483-7vrg","GO-2026-6308"],"modified":"2026-09-11T03:30:26.305466469Z","published":"2026-08-28T16:51:48.114Z","related":["openSUSE-SU-2026:21812-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55066.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-639"]},"references":[{"type":"WEB","url":"https://github.com/go-vikunja/vikunja/releases/tag/v2.4.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55066.json"},{"type":"ADVISORY","url":"https://github.com/go-vikunja/vikunja/security/advisories/GHSA-5pg6-m483-7vrg"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55066"},{"type":"FIX","url":"https://github.com/go-vikunja/vikunja/commit/36cdc2ce2be0b8ccc74227d178b92047d59cd65f"},{"type":"FIX","url":"https://github.com/go-vikunja/vikunja/pull/3239"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/go-vikunja/vikunja","events":[{"introduced":"0"},{"fixed":"36cdc2ce2be0b8ccc74227d178b92047d59cd65f"},{"fixed":"907850feae3866ae9b16ea1c7b84a4d77273415a"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"2.4.0"}]}}],"versions":["v2.3.0","v2.2.2","v2.2.1","v2.2.0","v2.1.0","v2.0.0","v1.1.0","v1.0.0","v1.0.0-rc4","v1.0.0-rc3","v1.0.0-rc2","v1.0.0-rc1","v1.0.0-rc0","v0.24.1","v0.23.0","v0.22.1","v0.22.0","v0.21.0","v0.20.4","v0.20.3","v0.20.1","v0.20.0","v0.19.2","v0.19.1","v0.19.0","v0.18.1","v0.18.0","v0.17.0","v0.16.0","v0.15.0","v0.14.0","v0.13","v0.12","v0.11","v0.10","v0.9","v0.8","v0.7","v0.6","v0.5","v0.4","v0.3","v0.2","v0.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55066.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N"}]}