{"id":"CVE-2026-57856","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-57856","generatedAt":"2026-10-28T03:42:52.412Z","title":"Cockpit CMS contains a path traversal vulnerability in the Bucket file storage API (/system/buckets/api).","description":"Cockpit CMS contains a path traversal vulnerability in the Bucket file storage API (/system/buckets/api). The api() method in modules/System/Controller/Buckets.php sanitizes the bucket name with preg_replace('/[^a-zA-Z0-9-_\\\\.]/','', $bucket), which permits '..' and '../' sequences. The sanitized value is interpolated into a Flysystem path as uploads://buckets/{bucket}. Flysystem's WhitespacePathNormalizer resolves 'buckets/..' to the empty string (the uploads storage root) without raising PathTraversalDetected because the '..' has a preceding component to consume. An authenticated low-privileged user can send a crafted request with a '../' bucket name to list, upload, and delete files across all buckets, including those belonging to other users or roles","published":"2026-07-13T23:16:47.000Z","lastModified":"2026-10-24T22:10:00.000Z","status":"Deferred","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":8.7,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-22"],"affected":[],"epss":{"score":0.00479,"percentile":0.4117,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.48%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://gist.github.com/sermikr0/821c4edd3c34e98a62a50b07707785bd","source":"disclosure@vulncheck.com"},{"url":"https://github.com/Cockpit-HQ/Cockpit/commit/dde2d1d74f5f4e11de42a298918ea8c9684f932c","source":"disclosure@vulncheck.com"},{"url":"https://github.com/cockpit-hq/cockpit","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/cockpit-cms-missing-authorization-in-bucket-file-storage-api","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/cockpit-cms-path-traversal-via-bucket-name-in-bucket-file-storage-api","source":"disclosure@vulncheck.com"},{"url":"https://gist.github.com/sermikr0/821c4edd3c34e98a62a50b07707785bd","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-57856","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}