CVE-2025-27614: Gitk Remote Code Execution Vulnerability

CVE-2025-27614 Overview

CVE-2025-27614 is a command injection vulnerability (CWE-78) in Gitk, the Tcl/Tk based Git history browser. Starting with version 2.41.0, a maliciously crafted Git repository can be used to trick users into executing arbitrary scripts supplied by an attacker. When a user who has cloned such a repository invokes gitk filename with a specially crafted filename structure, the attacker's script (such as Bourne shell, Perl, or Python) is executed with the privileges of the user.

Critical Impact
Successful exploitation allows attackers to execute arbitrary code on victim systems through social engineering, potentially leading to complete system compromise, data theft, or lateral movement within networks.

Affected Products

Gitk versions 2.41.0 through 2.43.6
Gitk versions 2.44.0 through 2.44.3
Gitk versions 2.45.0 through 2.45.3
Gitk versions 2.46.0 through 2.46.3
Gitk versions 2.47.0 through 2.47.2
Gitk versions 2.48.0 through 2.48.1
Gitk version 2.49.0

Discovery Timeline

2025-07-10 - CVE-2025-27614 published to NVD
2025-11-04 - Last updated in NVD database

Technical Details for CVE-2025-27614

Vulnerability Analysis

This vulnerability stems from improper input validation when Gitk processes filename arguments. When a user invokes gitk with a filename parameter, the application fails to properly sanitize the input before passing it to shell execution functions. An attacker can craft a filename with a specific structure that breaks out of the intended command context and executes arbitrary commands or scripts.

The vulnerability requires social engineering to be successful—an attacker must convince a victim to clone a malicious repository and then run gitk with a specially crafted filename argument. Despite requiring user interaction, the impact is severe as it allows full code execution with the victim's privileges.

Root Cause

The root cause is improper neutralization of special elements used in an OS command (CWE-78). The Gitk application does not adequately validate or sanitize filename arguments before incorporating them into command execution contexts. This allows specially structured filenames to inject and execute arbitrary shell commands or scripts when processed by the application.

Attack Vector

The attack follows a social engineering pattern combined with the technical exploit:

An attacker creates a malicious Git repository containing files with specially crafted names designed to exploit the command injection vulnerability
The attacker convinces a victim to clone this repository through legitimate-seeming channels (e.g., fake open source project, phishing)
The victim clones the repository and later runs gitk filename to view the history of a specific file
Due to improper input sanitization, the crafted filename structure causes Gitk to execute the attacker's embedded script
The malicious script runs with the victim's user privileges, potentially compromising the system

The vulnerability exploits the local attack vector, requiring the attacker to first deliver the malicious repository to the victim's system. Technical details and the specific fix can be found in the GitHub commit reference.

Detection Methods for CVE-2025-27614

Indicators of Compromise

Unexpected script execution originating from Gitk processes
Unusual child processes spawned by Gitk with suspicious command arguments
Files with unusual naming patterns in cloned Git repositories that contain shell metacharacters or script execution syntax
Network connections initiated by processes descended from Gitk

Detection Strategies

Monitor process execution chains for Gitk spawning unexpected child processes, particularly shell interpreters like /bin/sh, /usr/bin/perl, or /usr/bin/python
Implement file integrity monitoring on systems where developers frequently clone external repositories
Deploy endpoint detection rules to identify command injection patterns in process arguments related to Git operations
Review Git repository contents for files with suspicious naming conventions before opening with Gitk

Monitoring Recommendations

Enable enhanced process auditing to capture full command-line arguments for Git-related tools
Configure security monitoring to alert on Gitk processes that spawn shell interpreters or scripting engines
Implement repository scanning in CI/CD pipelines to detect potentially malicious file naming patterns
Monitor for unusual file system activity following Gitk invocations

How to Mitigate CVE-2025-27614

Immediate Actions Required

Upgrade Gitk to a patched version: 2.43.7, 2.44.4, 2.45.4, 2.46.4, 2.47.3, 2.48.2, 2.49.1, or 2.50
Audit recently cloned repositories from untrusted sources for suspicious file names
Educate developers about the risks of cloning repositories from untrusted sources and running Gitk with arbitrary filenames
Consider restricting Gitk usage to trusted repositories until patches are applied

Patch Information

The vulnerability has been addressed in multiple Gitk release branches. Users should upgrade to one of the following fixed versions:

Version 2.43.7 for the 2.43.x branch
Version 2.44.4 for the 2.44.x branch
Version 2.45.4 for the 2.45.x branch
Version 2.46.4 for the 2.46.x branch
Version 2.47.3 for the 2.47.x branch
Version 2.48.2 for the 2.48.x branch
Version 2.49.1 for the 2.49.x branch
Version 2.50 for the latest release

The fix can be reviewed in the GitHub commit. Additional details are available in the GitHub Security Advisory.

Workarounds

Avoid using gitk filename syntax with files from untrusted repositories until the patch is applied
Use alternative Git history viewing tools such as git log or web-based interfaces for repositories from untrusted sources
Implement repository isolation by cloning untrusted repositories in sandboxed environments or containers
Review file names in repositories before using Gitk to inspect file-specific history

bash

# Check current Gitk version
gitk --version

# Update Git (which includes Gitk) on Debian/Ubuntu
sudo apt update && sudo apt upgrade git

# Update Git on RHEL/CentOS/Fedora
sudo dnf update git

# Update Git on macOS with Homebrew
brew upgrade git