CVE-2026-57856
Cockpit CMS contains a path traversal vulnerability in the Bucket file storage API (/system/buckets/api).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.61%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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
- CVSS 4.0
- 8.7 HIGHCVSS: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
- EPSS
- 0.61% probability · 47th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- disclosure@vulncheck.com
References
- https://gist.github.com/sermikr0/821c4edd3c34e98a62a50b07707785bd
- https://github.com/Cockpit-HQ/Cockpit/commit/dde2d1d74f5f4e11de42a298918ea8c9684f932c
- https://github.com/cockpit-hq/cockpit
- https://www.vulncheck.com/advisories/cockpit-cms-missing-authorization-in-bucket-file-storage-api
- https://www.vulncheck.com/advisories/cockpit-cms-path-traversal-via-bucket-name-in-bucket-file-storage-api
- https://gist.github.com/sermikr0/821c4edd3c34e98a62a50b07707785bd
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.