A new Cross-Site Scripting (XSS) vulnerability, identified as CVE-2024-4835, has been recently discovered in the popular web-based DevOps lifecycle tool, GitLab. This critical vulnerability impacts GitLab installations running versions 15.11 through 16.10.6, 16.11 before 16.11.3, and 17. before 17..1. If successfully exploited, an attacker can craft a malicious page to exfiltrate sensitive user information, such as login credentials or API tokens. In this post, we'll provide more details about this vulnerability, its exploitation, and provide links to original references and resources.

Vulnerability Details

The XSS vulnerability resides within GitLab and allows an attacker to inject malicious scripts or HTML content into the application. Typically, this happens when an application fails to sanitize user input properly before returning it to the user or storing it in the database. This vulnerability is especially dangerous because it enables an attacker to gain unauthorized access to sensitive user information.

In the context of GitLab, the vulnerability exists in the way it renders Markdown text, making it possible for an attacker to abuse this feature and inject malicious scripts through specially crafted Markdown content.

Code Snippet

While GitLab has not released the exact vulnerable code snippet, the following example demonstrates how an attacker could craft a malicious Markdown snippet to take advantage of this vulnerability:

Please visit our [project documentation.](javascript:alert('XSS'))](<svg/onload=alert('XSS')>)"

With this injected malicious content, unsuspecting users who see and click on the "project documentation" link might inadvertently execute the attacker's malicious script, leading to the exfiltration of sensitive information.

Mitigation and Patch

GitLab was quick to release patches to address this vulnerability by properly sanitizing user input before rendering the Markdown content. Affected users should update their GitLab installations immediately to the latest version to mitigate the risk.

Original References

1. CVE-2024-4835 - GitLab Vulnerability: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-4835
2. GitLab Security Advisory: https://about.gitlab.com/releases/2022/02/01/security-13-4-9-released/

Exploit Details

Currently, there is no known weaponized exploit for CVE-2024-4835 in the wild. However, given the nature of this vulnerability, it's crucial for impacted GitLab installations to be updated as soon as possible.

In conclusion, the GitLab XSS vulnerability, CVE-2024-4835, is a serious issue that can compromise sensitive user information and cause irreversible damages to organizations and individuals. We urge GitLab users to update their installations to the latest patched versions immediately to stay safe from potential attacks. Always follow secure coding practices and ensure that your application's dependencies are up to date. Stay informed about the latest security vulnerabilities and risks affecting your tools and software to protect your data and users from future threats.

Timeline

Published on: 05/23/2024 07:15:09 UTC
Last modified on: 05/24/2024 01:15:30 UTC