Vulnerability · Published May 15, 2026 · Assigned by GitHub_M
CVE-2026-45539Microsoft APM: Symlinks under `.apm/prompts/` and `.apm/agents/` are dereferenced during `apm install`, copying host-local file contents into the project tree
High 7.4
In plain English
A high-severity information exposure in apm from microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Microsoft APM is an open-source, community-driven dependency manager for AI agents. From 0.5.4 to 0.12.4, two primitive integrators in apm-cli enumerate package files with bare Path.glob() / Path.rglob() calls and read each match with Path.read_text(), transparently following symbolic links. A symlink committed inside a remote APM dependency under .apm/prompts/<x>.prompt.md or .apm/agents/<x>.agent.md is preserved verbatim into apm_modules/ on clone and then dereferenced during integration, with the resolved content written as a regular file into the project's deploy directories. The package content_hash, the pre-deploy SecurityGate scan, and apm audit do not flag this. The deploy roots are not added to the auto-generated .gitignore, so the resulting files are staged by git add by default. This vulnerability is fixed in 0.13.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | apm | 0.13.0 | GHSA-q5pp-gvjg-h7v4 |
| PyPI | apm | 0.13.0 | PYSEC-2026-2377 |
Affected products (as reported)
Weakness: CWE-59, CWE-200 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
References
- https://github.com/microsoft/apm/security/advisories/GHSA-q5pp-gvjg-h7v4 x_refsource_CONFIRM