A recent CVE (Common Vulnerabilities and Exposures) entry has come to light that presents a DoS (Denial-of-Service) vulnerability in the KAS (Kubernetes Agent Server) of GitLab CE/EE. This vulnerability affects all GitLab versions from 16.10. before 16.10.6 and 16.11. before 16.11.3. In this post, we'll dive deeper into this vulnerability (CVE-2024-5469) and examine how an attacker can crash the KAS by sending crafted gRPC requests.

Background

GitLab is an open-source web application that provides a complete DevOps platform, covering everything from source code management to CI/CD, monitoring, and security. GitLab CE/EE is the Community Edition (CE) and Enterprise Edition (EE) of GitLab, which are both self-hosted solutions. KAS is a component of GitLab that serves as a communication bridge between GitLab and Kubernetes clusters. gRPC is a modern, high-performance communication protocol utilized by KAS for efficient communication.

Exploit Details

The vulnerability CVE-2024-5469 is focused on the denial-of-service through the KAS component and potentially affects any organization using GitLab CE/EE versions 16.10. before 16.10.6 and 16.11. before 16.11.3. By crafting malicious gRPC requests, an attacker can crash the KAS, subsequently causing disruptions or complete denial of service for affected GitLab users.

An example scenario, highlighting the risk imposed by this vulnerability, is shown in the code snippet below:

// Attacker creates a malicious gRPC request
grpc_request = craft_malicious_grpc_request() 

// The crafted request is sent to KAS resulting in crashing the server
send_to_kas(grpc_request)

For developers and security personnel aiming to mitigate this vulnerability, it is highly recommended to patch your GitLab instances by upgrading to version 16.10.6, 16.11.3, or later.

1. CVE-2024-5469 - NVD Entry
2. GitLab Official Security Advisory
3. GitLab Releases and Patch Instructions

Conclusion

As technology progresses, software vulnerabilities continue to rise and pose threats to individuals and organizations alike. It is essential for software developers and users always to stay up-to-date with the latest security patches to ensure their systems' integrity. In the case of CVE-2024-5469, updating GitLab CE/EE to the latest patched version (16.10.6, 16.11.3, or later) is vital to mitigate the risk of denial-of-service attacks through KAS.

Stay safe and always be vigilant about the security of your systems!

Timeline

Published on: 06/14/2024 04:15:43 UTC
Last modified on: 06/17/2024 12:42:04 UTC