Open WebUI: Sibling-Prefix Path Traversal via /cache/{path}

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2026-54014: 0.36% estimated exploitation activity in the next 30 days; percentile 29.93 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A path traversal vulnerability exists in open-webui's cache file serving endpoint that allows any authenticated user to read files from sibling directories outside the intended cache directory, by exploiting an incomplete startswith containment check that lacks a trailing path separator. The root cause is that servecachefile() in openwebui/main.py validates the resolved path with filepath.startswith(os.path.abspath(CACHEDIR)) — without appending os.sep. This allows any path resolving to a sibling directory whose name begins with cache (e.g. cachesibling, cachebackup, cachedmodels) to pass validation. Deep traversal and absolute paths are correctly blocked. The bypass is narrow but confirmed — limited to sibling-prefix directories. Exploitation constraints | Constraint | Detail | |---|---| | Auth required | getverifieduser — any user with role user or admin | | Scope | Only sibling directories starting with cache (e.g. cachebackup, cachedmodels) | | Deep traversal | Blocked —…

Published by the source

17 Jun 2026, 14:16 UTC

Last modified by the source

20 Jul 2026, 21:15 UTC

Source last checked

26 Oct 2026, 13:49 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-j2c8-v969-8r5c

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-j2c8-v969-8r5c

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# Patch Next advisory brief: CVE-2026-54014

Advisory: Open WebUI: Sibling-Prefix Path Traversal via /cache/{path}
IDs: CVE-2026-54014, GHSA-j2c8-v969-8r5c
Record: https://patchnext.com/advisories/cve-2026-54014 (revision 2, source checked 26 Oct 2026, 13:49 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: open-webui 0.9.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI open-webui: affected <= 0.9.5; fixed in 0.9.6

## Suggested inspection (read-only)
- `python -m pip show open-webui`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on open-webui.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-j2c8-v969-8r5c (OSV record GHSA-j2c8-v969-8r5c lists affected ranges: PyPI open-webui >=0 <0.9.6 (fixed))
- Verified: https://github.com/advisories/GHSA-j2c8-v969-8r5c (GitHub-reviewed advisory GHSA-j2c8-v969-8r5c lists affected ranges: PyPI open-webui >=0 <=0.9.5)

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