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.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - 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. (CVE-2026-42563)

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-42563)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
442449	SCA: security update for dulwich (GHSA-9277-mp7x-85jf)	Tenable Cloud Security	SCA Checks	high
442449	SCA: security update for dulwich (GHSA-9277-mp7x-85jf)	Tenable Self-Hosted Container Security	SCA Checks	high
317718	Linux Distros Unpatched Vulnerability : CVE-2026-42563	Nessus	Misc.	high

Detections

Analytics

CVE-2026-42563

high

Tenable Plugins

high

high

high