Microsoft APM CLI's plugin.json component paths escape plugin root and copy arbitrary host files during install

Exploitation

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

CVSS

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

EPSS

• CVE-2026-44641: 0.43% estimated exploitation activity in the next 30 days; percentile 37.04 (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 Microsoft APM normalizes marketplace plugins by copying plugin components referenced in plugin.json into .apm/. The manifest fields agents, skills, commands, and hooks are attacker-controlled, but the implementation does not enforce that those paths remain inside the plugin directory. A malicious plugin can therefore use absolute paths or ../ traversal paths to copy arbitrary readable host files or directories from the installer's machine during apm install. In the verified primary proof of concept, a malicious plugin sets plugin.json.commands to an external markdown file. A single apm install copies that outside file into .apm/prompts/ and then auto-integrates it into .github/prompts/secret.prompt.md in the victim project. This is a local supply-chain trust-boundary violation with direct confidentiality and integrity impact. Reviewed version and commit: - apm-cli version 0.8.11 - main commit 70b34faa16a5a783424698163deeb028854fd23a Details Root cause: -…

Published by the source

7 May 2026, 21:41 UTC

Last modified by the source

13 Jul 2026, 16:43 UTC

Source last checked

26 Oct 2026, 13:41 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-xhrw-5qxx-jpwr

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-xhrw-5qxx-jpwr

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# Patch Next advisory brief: CVE-2026-44641

Advisory: Microsoft APM CLI's plugin.json component paths escape plugin root and copy arbitrary host files during install
IDs: CVE-2026-44641, GHSA-xhrw-5qxx-jpwr
Record: https://patchnext.com/advisories/cve-2026-44641 (revision 2, source checked 26 Oct 2026, 13:41 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: apm-cli 0.8.12. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI apm-cli: affected <= 0.8.11; fixed in 0.8.12

## Suggested inspection (read-only)
- `python -m pip show apm-cli`: 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 apm-cli.
- 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-xhrw-5qxx-jpwr (OSV record GHSA-xhrw-5qxx-jpwr lists affected ranges: PyPI apm-cli >=0 <0.8.12 (fixed))
- Verified: https://github.com/advisories/GHSA-xhrw-5qxx-jpwr (GitHub-reviewed advisory GHSA-xhrw-5qxx-jpwr lists affected ranges: PyPI apm-cli >=0 <=0.8.11)

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