PyLoad vulnerable to Path Traversal via Package Folder Name in set_package_data

Exploitation

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

CVSS

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

EPSS

• CVE-2026-42315: 0.40% estimated exploitation activity in the next 30 days; percentile 33.76 (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 No sanitization of package folder name allows writing files anywhere outside the intended download directory. Affected Component - src/pyload/core/api/init.py - Function: setpackagedata() Details When passing a folder name in the setpackagedata() API function call inside the data object with key "folder", there is no sanitization at all, allowing a user with Perms.MODIFY to specify arbitrary directories as download locations for a package. PoC 1) Create a package, note response package ID e.g. 5 2) Call setpackagedata for this package ID with an arbitrary directory 3) New download folder will be set without any checks Response: Impact Allows Absolute Path Traversal to write in an arbitrary directory as long as the pyLoad process has write access.

Published by the source

5 May 2026, 21:18 UTC

Last modified by the source

8 Jun 2026, 20:00 UTC

Source last checked

26 Oct 2026, 13:44 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-838g-gr43-qqg9

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-838g-gr43-qqg9

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# Patch Next advisory brief: CVE-2026-42315

Advisory: PyLoad vulnerable to Path Traversal via Package Folder Name in set_package_data
IDs: CVE-2026-42315, GHSA-838g-gr43-qqg9
Record: https://patchnext.com/advisories/cve-2026-42315 (revision 2, source checked 26 Oct 2026, 13:44 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: pyload-ng 0.5.0b3.dev100. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI pyload-ng: affected <= 0.5.0b3.dev99; fixed in 0.5.0b3.dev100

## Suggested inspection (read-only)
- `python -m pip show pyload-ng`: 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 pyload-ng.
- 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-838g-gr43-qqg9 (OSV record GHSA-838g-gr43-qqg9 lists affected ranges: PyPI pyload-ng >=0 <0.5.0b3.dev100 (fixed))
- Verified: https://github.com/advisories/GHSA-838g-gr43-qqg9 (GitHub-reviewed advisory GHSA-838g-gr43-qqg9 lists affected ranges: PyPI pyload-ng >=0 <=0.5.0b3.dev99)

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