CVE-2026-46383: Arbitrary File Overwrite via Path Traversal (TarSlip) in Microsoft APM

Vulnerability ID: CVE-2026-46383

CVSS Score: 5.5

Published: 2026-05-15

A path traversal vulnerability exists in the legacy-bundle probing logic of Microsoft APM, an open-source dependency manager for AI agents. On Windows systems using Python versions prior to 3.12, this allows local attackers to overwrite arbitrary files via a crafted tarball.

TL;DR

Microsoft APM < 0.13.0 on Windows is vulnerable to an arbitrary file overwrite during archive extraction. Exploitation requires user interaction to install a crafted tarball.

⚠️ Exploit Status: POC

Technical Details

CVE ID : CVE-2026-46383

CWE ID : CWE-22

CVSS Score : 5.5

Attack Vector : Local (User Interaction Required)

Impact : High Integrity (Arbitrary File Overwrite)

Exploit Status : Proof of Concept

CISA KEV : Not Listed

Affected Systems

Microsoft APM on Windows environments using Python < 3.12

microsoft/apm : < 0.13.0 (Fixed in: 0.13.0 )

Code…