No exploitation reportedFix available

CVE-2026-45539

Q: Is CVE-2026-45539 actively exploited?

Active exploitation of CVE-2026-45539 has not been confirmed. Its EPSS score was 1.1% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2026-45539?

CVE-2026-45539 has a CVSS v3 base score of 7.4 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N.

No exploitation reported by the sources we read.

Published2026-05-15
Fixed in0.13.0
WeaknessCWE-200 · CWE-59

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC

2026-05-1517:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-45539?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-45539?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

OSV

apm

Branch	Affected	Fixed in	Source
0.x	≥ 0.5.4, < 0.13.0	0.13.0	OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update apm to 0.13.0

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVE recordread 2026-10-23
CISA-ADPSSVC decisionnone2026-05-15
OpenCVESSVC decisionnone—
CNACVSS 3.17.4read 2026-10-23
CNAweakness (CWE)CWE-200, CWE-59read 2026-10-23
FIRST EPSSEPSS score1.1 %2026-10-22
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
Published: 2026-05-15
Last Modified: 2026-06-17
NVD status: Deferred

Frequently asked questions

What is CVE-2026-45539?

Is CVE-2026-45539 actively exploited?

Active exploitation of CVE-2026-45539 has not been confirmed. Its EPSS score was 1.1% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-45539?

CVE-2026-45539 has a CVSS v3 base score of 7.4 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N.

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