CVE-2021-25138 : Security Advisory and Response

A buffer overflow vulnerability has been identified in the Baseboard Management Controller (BMC) firmware of several HPE Cloudline servers, potentially allowing local attackers to execute arbitrary code or disrupt the system.

Understanding CVE-2021-25138

This CVE describes a specific vulnerability in the BMC firmware of HPE Cloudline servers that could be exploited by attackers to cause a buffer overflow in the spx_restservice uploadsshkey function.

What is CVE-2021-25138?

The vulnerability in the BMC firmware of HPE Cloudline servers could lead to a buffer overflow situation in the spx_restservice uploadsshkey function, enabling local attackers to execute arbitrary code and potentially disrupt the normal operation of the servers.

The Impact of CVE-2021-25138

If successfully exploited, this vulnerability could allow malicious actors to gain unauthorized access to the affected servers, manipulate data, disrupt services, or even cause a complete system compromise, posing a significant security risk to organizations using these servers.

Technical Details of CVE-2021-25138

This section provides more technical insights into the vulnerability, including its description, affected systems, and the exploitation mechanism.

Vulnerability Description

The buffer overflow vulnerability in the BMC firmware of HPE Cloudline servers arises due to insufficient input validation on the spx_restservice uploadsshkey function, potentially allowing attackers to write beyond the allocated memory buffers, leading to code execution or crashes.

Affected Systems and Versions

The vulnerability affects multiple HPE Cloudline server models including CL5800 Gen9, CL5200 Gen9, CL4100 Gen10, CL3100 Gen10, and CL5800 Gen10 running specific firmware versions like Version 1.09.0.0, 1.07.0.0, 1.10.0.0, and 1.08.0.0.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted requests to the uploadsshkey function, triggering a buffer overflow condition that may allow them to execute arbitrary code with elevated privileges.

Mitigation and Prevention

Here are some steps to mitigate the risks associated with CVE-2021-25138 and secure the affected HPE Cloudline servers.

Immediate Steps to Take

Update the BMC firmware to a non-vulnerable version provided by HPE.
Implement network-level controls to restrict access to the affected BMC interfaces.
Monitor system logs for any unusual activities that may indicate exploitation attempts.

Long-Term Security Practices

Regularly update firmware and software components to patch known vulnerabilities.
Conduct regular security audits and assessments to identify and address potential risks proactively.

Patching and Updates

Stay informed about security advisories from HPE and promptly apply patches or updates to eliminate vulnerabilities and enhance the overall security posture of the servers.