GitLab XSS Vulnerability CVE-2025-6948: Malicious Content Injection Risk

Introduction

A critical security flaw, CVE-2025-6948, has been identified in GitLab's Community Edition (CE) and Enterprise Edition (EE), posing significant risks through cross-site scripting (XSS). This vulnerability allows attackers to execute unauthorized actions by injecting malicious content, potentially compromising user accounts and sensitive data.

Technical Information

CVE-2025-6948 is classified under CWE-79, indicating improper neutralization of input during web page generation. The vulnerability occurs when user-supplied input is inadequately sanitized, allowing attackers to inject malicious JavaScript payloads into GitLab's web interface elements such as issue comments, repository descriptions, or CI/CD pipeline configurations.

Attackers exploit this vulnerability by crafting malicious scripts that execute in the context of authenticated user sessions. When a victim interacts with compromised content, the injected scripts execute with the victim's permissions, enabling unauthorized actions such as privilege escalation, data manipulation, or repository compromise.

Attack Vectors and Exploitation Methods

Attackers typically exploit CVE-2025-6948 through stored or reflected XSS attacks:

Stored XSS: Malicious scripts are embedded in persistent GitLab elements, executing whenever users access affected content.
Reflected XSS: Attackers trick users into clicking crafted links containing malicious scripts, executing the payload upon interaction.

Patch Information

In the latest GitLab patch release (versions 18.1.2, 18.0.4, and 17.11.6), several critical security vulnerabilities have been addressed to enhance the platform's security posture:

Cross-Site Scripting (XSS) Vulnerability (CVE-2025-6948): Stricter input validation and output encoding mechanisms have been implemented to prevent unauthorized script execution.
Improper Authorization for Forking Restrictions (CVE-2025-3396): Proper authorization checks within the API ensure consistent application of forking restrictions.
Bypassing Group-Level User Invitation Restrictions (CVE-2025-4972 & CVE-2025-6168): Enhanced validation and authorization controls have been introduced to uphold invitation restrictions.
rsync Security Updates: Updated to version 3.4.1, addressing vulnerabilities CVE-2024-12084 and CVE-2024-12088.

These patches collectively strengthen GitLab's defenses against unauthorized access and potential exploits.

Affected Systems and Versions

The vulnerability specifically affects the following GitLab versions:

GitLab CE/EE versions 17.11 before 17.11.6
GitLab CE/EE versions 18.0 before 18.0.4
GitLab CE/EE versions 18.1 before 18.1.2

Vendor Security History

GitLab has a robust security program, regularly addressing vulnerabilities through timely patches and a proactive bug bounty program. Previous XSS vulnerabilities, such as CVE-2025-0376 and CVE-2025-2443, were rapidly addressed, demonstrating GitLab's commitment to security.

References

Immediate action is recommended to mitigate this critical vulnerability and protect your GitLab environment.

Source: This report was created using AI

If you have suggestions for improvement or feedback, please reach out to us at [email protected]