CVE-2021-28209 : Exploit Details and Defense Strategies

This article discusses the vulnerability in ASUS BMC's firmware where the Delete video file function allows remote attackers to access system files via path traversal.

Understanding CVE-2021-28209

This section provides insights into the impact and technical details of the CVE.

What is CVE-2021-28209?

The vulnerability in ASUS BMC's firmware allows remote attackers to access system files via path traversal by exploiting the Delete video file function.

The Impact of CVE-2021-28209

The vulnerability poses a medium severity risk with a CVSS base score of 4.9. It can lead to high confidentiality impact without requiring user interaction.

Technical Details of CVE-2021-28209

This section covers the vulnerability description, affected systems, and exploitation mechanism.

Vulnerability Description

The specific function in ASUS BMC's firmware Web management page does not filter the specific parameter, enabling path traversal attacks.

Affected Systems and Versions

Several ASUS BMC firmware versions are affected, including 1.09, 1.10.0, 1.10.3, 1.11.5, and others.

Exploitation Mechanism

Remote attackers can exploit the vulnerability by using path traversal to access system files after obtaining administrator permissions.

Mitigation and Prevention

This section outlines immediate steps and long-term security practices to prevent exploitation.

Immediate Steps to Take

Update BMC's firmwares to the recommended versions, including ESC4000 G4X 1.15.6, RS100-E10-PI2 1.15.3, RS720-E9-RS24-U 1.14.3, and others.

Long-Term Security Practices

Regularly update firmware and apply security patches to mitigate future vulnerabilities, ensuring system integrity and confidentiality.

Patching and Updates

Stay informed on firmware updates and security advisories from ASUS to address any newly discovered vulnerabilities.