CVE-2023-2199 : Exploit Details and Defense Strategies

This article discusses the details of CVE-2023-2199, a vulnerability discovered in GitLab CE/EE affecting multiple versions.

Understanding CVE-2023-2199

CVE-2023-2199 is a vulnerability in GitLab CE/EE that allows for a Regular Expression Denial of Service by sending specially crafted payloads to the preview_markdown endpoint.

What is CVE-2023-2199?

The vulnerability in GitLab CE/EE versions starting from 12.0 before 15.10.8, starting from 15.11 before 15.11.7, and starting from 16.0 before 16.0.2, allows for uncontrolled resource consumption, leading to a denial of service through crafted payloads.

The Impact of CVE-2023-2199

This vulnerability poses a high severity threat with a CVSS v3.1 base score of 7.5 out of 10. An attacker can potentially exploit this issue to cause a denial of service, impacting the availability of the GitLab service.

Technical Details of CVE-2023-2199

The technical details of CVE-2023-2199 provide insights into the vulnerability, affected systems, and the exploitation mechanism.

Vulnerability Description

The vulnerability in GitLab CE/EE versions allows for uncontrolled resource consumption, leading to denial of service by sending specially crafted payloads to the preview_markdown endpoint.

Affected Systems and Versions

GitLab CE/EE versions starting from 12.0 before 15.10.8, starting from 15.11 before 15.11.7, and starting from 16.0 before 16.0.2 are affected by CVE-2023-2199.

Exploitation Mechanism

Exploiting this vulnerability involves sending crafted payloads to the preview_markdown endpoint in affected GitLab versions, ultimately causing a Regular Expression Denial of Service.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-2199, immediate steps should be taken while incorporating long-term security practices.

Immediate Steps to Take

Update affected GitLab instances to versions 15.10.8, 15.11.7, and 16.0.2 or higher.
Monitor and restrict access to the preview_markdown endpoint.
Implement network-level protections to mitigate potential denial-of-service attacks.

Long-Term Security Practices

Regularly update GitLab software to stay protected against known vulnerabilities.
Conduct security assessments and penetration testing to identify and address security gaps.
Educate users and developers on secure coding practices to prevent future vulnerabilities.

Patching and Updates

GitLab has released patches addressing CVE-2023-2199 in versions 15.10.8, 15.11.7, and 16.0.2 to mitigate the vulnerability and enhance system security. It is recommended to apply these patches promptly to secure affected systems.