CVE-2021-27796 Explained : Impact and Mitigation

A vulnerability in Brocade Fabric OS versions before Brocade Fabric OS v8.0.1b, v7.4.1d could allow an authenticated attacker within the restricted shell environment (rbash) to read the contents of any file on the filesystem using specific binaries.

Understanding CVE-2021-27796

This CVE involves a privilege escalation vulnerability in Brocade Fabric OS versions that could be exploited by an authenticated attacker to gain unauthorized access to sensitive files.

What is CVE-2021-27796?

CVE-2021-27796 is a privilege escalation vulnerability in Brocade Fabric OS versions prior to v8.0.1b and v7.4.1d. It enables an authenticated attacker in the restricted shell environment to read arbitrary file contents through certain binaries.

The Impact of CVE-2021-27796

This vulnerability poses a significant risk as it allows an attacker to access potentially confidential information stored on the filesystem, leading to data exposure and potential exploitation.

Technical Details of CVE-2021-27796

In Brocade Fabric OS versions before v8.0.1b, v7.4.1d, an authenticated attacker, under the 'user' or 'factory' account, can exploit rbash to read any file contents using specific binaries.

Vulnerability Description

The vulnerability enables unauthorized file read operations within the rbash environment, potentially exposing critical system files to malicious actors.

Affected Systems and Versions

Brocade Fabric OS versions prior to v8.0.1b and v7.4.1d are affected by this privilege escalation vulnerability, putting systems running these versions at risk.

Exploitation Mechanism

By leveraging the restricted shell environment and specific binaries, an authenticated attacker can bypass file system restrictions to read sensitive data.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-27796, immediate action should be taken to secure affected systems and prevent unauthorized access.

Immediate Steps to Take

Users are advised to update Brocade Fabric OS to version v8.0.1b or higher to eliminate the vulnerability and enhance system security.

Long-Term Security Practices

Implement stringent access controls, monitor file system activities, and conduct regular security audits to prevent similar privilege escalation attacks in the future.

Patching and Updates

Stay informed about security patches released by Brocade and ensure timely installation of updates to address known vulnerabilities and protect your systems.