CVE-2021-35938 : Security Advisory and Response

A symbolic link issue in RPM allows a local unprivileged user to escalate their privileges by exchanging a file with a symbolic link to a security-critical file. This article provides insights into the impact, technical details, and mitigation strategies of CVE-2021-35938.

Understanding CVE-2021-35938

This section delves into the details of the CVE-2021-35938 vulnerability.

What is CVE-2021-35938?

CVE-2021-35938 is a symbolic link issue in RPM that arises when RPM sets permissions and credentials post file installation. This flaw enables a local unprivileged user to elevate privileges by replacing a file with a symbolic link pointing to a security-critical file, posing risks to data confidentiality, integrity, and system availability.

The Impact of CVE-2021-35938

The primary threat of CVE-2021-35938 lies in the compromise of data confidentiality, integrity, and system availability due to unauthorized privilege escalation.

Technical Details of CVE-2021-35938

Explore the technical aspects of the CVE-2021-35938 vulnerability.

Vulnerability Description

The vulnerability allows a local unprivileged user to switch the original file with a symbolic link to a security-critical file, leading to privilege escalation.

Affected Systems and Versions

RPM versions prior to v4.18.0 are affected by CVE-2021-35938. The issue has been addressed in rpm v4.18.0.

Exploitation Mechanism

By leveraging the symbolic link issue in RPM, a local unprivileged user can manipulate files to gain elevated privileges.

Mitigation and Prevention

Learn how to mitigate and prevent the CVE-2021-35938 vulnerability.

Immediate Steps to Take

Users are advised to update RPM to version 4.18.0 or later to mitigate the vulnerability and prevent unauthorized privilege escalation.

Long-Term Security Practices

Implement access controls and file system permissions to restrict unauthorized access and prevent privilege escalation attempts.

Patching and Updates

Regularly apply security patches and updates to RPM to address vulnerabilities and enhance system security.