CVE-2024-56731: Gogs Remote Code Execution Vulnerability

CVE-2024-56731 Overview

CVE-2024-56731 is a critical remote command execution vulnerability affecting Gogs, an open source self-hosted Git service. This vulnerability exists due to an insufficient patch for CVE-2024-39931, which still allows attackers to delete files under the .git directory and achieve remote command execution. Unprivileged user accounts can exploit this flaw to execute arbitrary commands on the Gogs instance with the privileges of the account specified by RUN_USER in the configuration, potentially allowing attackers to access and alter any users' code hosted on the same instance.

Critical Impact

Remote command execution allowing unprivileged users to execute arbitrary commands and access or modify any users' code hosted on the Gogs instance.

Affected Products

• Gogs versions prior to 0.13.3

Discovery Timeline

• 2025-06-24 - CVE CVE-2024-56731 published to NVD
• 2025-08-21 - Last updated in NVD database

Technical Details for CVE-2024-56731

Vulnerability Analysis

This vulnerability represents an incomplete security fix for the previously disclosed CVE-2024-39931. The original patch intended to prevent malicious file operations within the .git directory, but the implementation left gaps that still allowed attackers to delete files in this sensitive location. By manipulating files within the .git directory, an attacker can compromise the integrity of Git repositories and ultimately achieve arbitrary command execution on the underlying server.

The vulnerability is classified under CWE-552 (Files or Directories Accessible to External Parties), indicating that the application fails to properly restrict access to sensitive file system paths. The attack can be executed remotely over the network without requiring any authentication or user interaction, making it particularly dangerous for publicly accessible Gogs instances.

Root Cause

The root cause lies in insufficient input validation when handling file paths in the repository editor functionality. The original patch for CVE-2024-39931 did not adequately cover all code paths that interact with the .git directory, leaving the GetDiffPreview function and file deletion operations vulnerable to path traversal attacks that could target sensitive Git metadata files.

Attack Vector

The attack exploits the repository editor functionality in Gogs. An attacker with an unprivileged user account can craft malicious requests that bypass the existing path validation checks to manipulate files within the .git directory. By strategically deleting or modifying Git hooks or other configuration files within this directory, the attacker can achieve command execution when certain Git operations are triggered, running with the privileges of the RUN_USER account configured in Gogs.

 
 // GetDiffPreview produces and returns diff result of a file which is not yet committed.
 func (repo *Repository) GetDiffPreview(branch, treePath, content string) (diff *gitutil.Diff, err error) {
+	// 🚨 SECURITY: Prevent uploading files into the ".git" directory
+	if isRepositoryGitPath(treePath) {
+		return nil, errors.Errorf("bad tree path %q", treePath)
+	}
+
 	repoWorkingPool.CheckIn(com.ToStr(repo.ID))
 	defer repoWorkingPool.CheckOut(com.ToStr(repo.ID))

Source: GitHub Commit Update

Detection Methods for CVE-2024-56731

Indicators of Compromise

• Unexpected modifications or deletions of files within .git directories across repositories
• Anomalous user activity from unprivileged accounts attempting to access Git metadata files
• Unusual command execution events tied to the RUN_USER account configured in Gogs
• Web server logs showing suspicious requests targeting repository editor endpoints with .git path components

Detection Strategies

• Monitor Gogs application logs for file operation requests containing .git path segments
• Implement file integrity monitoring on .git directories within hosted repositories
• Audit user actions in Gogs for unusual repository editing patterns, especially from newly created or low-privilege accounts
• Deploy network intrusion detection rules to flag HTTP requests with path traversal patterns targeting Git metadata

Monitoring Recommendations

• Enable verbose logging in Gogs to capture all repository editing operations
• Set up alerts for any file system operations within .git directories on the Gogs server
• Regularly review process execution logs for unexpected commands running as the RUN_USER account

How to Mitigate CVE-2024-56731

Immediate Actions Required

• Upgrade Gogs to version 0.13.3 or later immediately
• Review repository editor access controls and consider restricting editing capabilities until patched
• Audit existing repositories for any signs of .git directory tampering
• Review server logs for evidence of exploitation attempts

Patch Information

The Gogs development team has addressed this vulnerability in version 0.13.3. The patch adds explicit security checks in the GetDiffPreview function and other file operation handlers to reject any requests targeting paths within the .git directory structure. Organizations should apply this update immediately by downloading the latest release from the GitHub Release v0.13.3 page. Additional details about the security fix can be found in the GitHub Security Advisory GHSA-wj44-9vcg-wjq7.

Workarounds

• Restrict repository editing capabilities at the reverse proxy level by blocking requests containing .git in the path
• Implement network-level controls to limit access to Gogs instances from untrusted networks
• Consider running Gogs with minimal RUN_USER privileges and in a containerized environment to limit the blast radius of potential exploitation

# Example nginx configuration to block .git path access in repository editor
location ~* /.*/_edit/.*\.git.* {
    deny all;
    return 403;
}

location ~* /.*/_delete/.*\.git.* {
    deny all;
    return 403;
}