Home

Description

Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich's `ProcessMergeDriver` substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the `%P` placeholder and executes it with `subprocess.run(..., shell=True)`. An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue.

PUBLISHED Reserved 2026-04-28 | Published 2026-06-10 | Updated 2026-06-10 | Assigner GitHub_M




HIGH: 7.7CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Problem types

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Product status

>= 0.24.0, < 1.2.5
affected

References

github.com/...ulwich/security/advisories/GHSA-9277-mp7x-85jf

github.com/...ommit/e3331b3b3a122fc313460182f928f59723580b7b

github.com/jelmer/dulwich/releases/tag/dulwich-1.2.5

cve.org (CVE-2026-42563)

nvd.nist.gov (CVE-2026-42563)

Download JSON