CVE-2026-87817

GitPython before 3.1.60 fails to properly validate the location of the git directory, which lets an attacker impersonate it using tracked files such as gitdir, commondir, and HEAD. An attacker who can get a victim to clone or open a crafted repository can plant a malicious pre-commit hook in the tracked hooks directory. When the victim's code then calls index.commit() on that repository, the hook executes, giving the attacker arbitrary code execution with the privileges of the process running GitPython. Anyone running affected versions in workflows that process untrusted or attacker-influenced repositories — such as CI/CD pipelines, automation, and developer tooling — is affected, while purely local, fully trusted repository use is largely out of scope. No public proof-of-concept is known, the issue is not in CISA KEV, and no in-the-wild exploitation has been reported.

What to do: Upgrade GitPython to 3.1.60 or later. As interim mitigation, avoid calling index.commit() or other hook-triggering operations on repositories cloned from untrusted sources, and audit dependency trees and CI images for GitPython versions below 3.1.60. When reviewing untrusted repositories, look for tracked files named gitdir, commondir, or HEAD and unexpected files in a tracked hooks directory.