CVE-2018-17456 Explained : Impact and Mitigation

Git versions prior to 2.14.5, between 2.15.x and 2.15.3, between 2.16.x and 2.16.5, between 2.17.x and 2.17.2, between 2.18.x and 2.18.1, and between 2.19.x and 2.19.1 are vulnerable to remote code execution during a recursive 'git clone' operation.

Understanding CVE-2018-17456

This CVE identifies a security vulnerability in Git that allows for remote code execution under specific conditions.

What is CVE-2018-17456?

Git versions mentioned are susceptible to remote code execution during the processing of a recursive 'git clone' of a superproject, triggered by a specific condition in the .gitmodules file.

The Impact of CVE-2018-17456

The vulnerability enables remote attackers to execute arbitrary code when a recursive 'git clone' operation is being processed, specifically when the .gitmodules file contains a URL field starting with a '-' character.

Technical Details of CVE-2018-17456

Git's vulnerability details and affected systems.

Vulnerability Description

The flaw in Git versions allows remote code execution during the processing of a recursive 'git clone' operation if a .gitmodules file has a URL field starting with a '-' character.

Affected Systems and Versions

Versions prior to 2.14.5
Between 2.15.x and 2.15.3
Between 2.16.x and 2.16.5
Between 2.17.x and 2.17.2
Between 2.18.x and 2.18.1
Between 2.19.x and 2.19.1

Exploitation Mechanism

The vulnerability is exploited by initiating a recursive 'git clone' operation of a superproject with a .gitmodules file containing a URL field starting with a '-' character.

Mitigation and Prevention

Steps to mitigate and prevent the CVE-2018-17456 vulnerability.

Immediate Steps to Take

Update Git to versions beyond the vulnerable ranges mentioned.
Avoid recursive 'git clone' operations with .gitmodules files containing URLs starting with '-' characters.

Long-Term Security Practices

Regularly update Git to the latest secure versions.
Implement secure coding practices to prevent code execution vulnerabilities.

Patching and Updates

Apply patches provided by Git to address the vulnerability.