motionEye has an Arbitrary File Read via Path Traversal in Picture/Movie Preview Endpoint

Exploitation

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

CVSS

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

EPSS

• CVE-2026-31978: 0.34% estimated exploitation activity in the next 30 days; percentile 27.02 (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 motionEye v0.43.1 (latest stable) is vulnerable to path traversal in the picture and movie API endpoints, like /picture/{id}/preview/{filename}. Neither the API handlers, nor the mediafiles.py functions like getmediapreview() check for .. sequences in the filename parameter, except getmediacontent() which does. This allows an authenticated user with normal (non-admin) privileges to read arbitrary files from the filesystem as the motionEye process user. Details The getmediacontent() function properly validates the path: But getmediapreview() does NOT: Similarly, delmediacontent() at line ~865 is also missing the check. This is a classic inconsistent fix pattern. The exploit requires %2F-encoded slashes (..%2F..%2F) which Tornado's URL router does NOT normalize — it passes the raw ../ through to os.path.join(). PoC Step 1: Authenticate as any user (normal or admin). Step 2: Compute the request signature. motionEye uses HMAC-style signatures for API authentication. The signature…

Published by the source

22 Jun 2026, 17:10 UTC

Last modified by the source

13 Jul 2026, 16:43 UTC

Source last checked

26 Oct 2026, 13:46 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-g9fx-5r4h-pcw3

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-g9fx-5r4h-pcw3

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# Patch Next advisory brief: CVE-2026-31978

Advisory: motionEye has an Arbitrary File Read via Path Traversal in Picture/Movie Preview Endpoint
IDs: CVE-2026-31978, GHSA-g9fx-5r4h-pcw3
Record: https://patchnext.com/advisories/cve-2026-31978 (revision 2, source checked 26 Oct 2026, 13:46 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: motioneye 0.44.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI motioneye: affected < 0.44.0; fixed in 0.44.0

## Suggested inspection (read-only)
- `python -m pip show motioneye`: 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 motioneye.
- 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-g9fx-5r4h-pcw3 (OSV record GHSA-g9fx-5r4h-pcw3 lists affected ranges: PyPI motioneye >=0 <0.44.0 (fixed))
- Verified: https://github.com/advisories/GHSA-g9fx-5r4h-pcw3 (GitHub-reviewed advisory GHSA-g9fx-5r4h-pcw3 lists affected ranges: PyPI motioneye >=0 <0.44.0)

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