CVE-2021-32554 : Exploit Details and Defense Strategies

A security vulnerability, tracked as CVE-2021-32554, has been identified in the 'apport' package by Canonical. This CVE allows local attackers to access sensitive data by exploiting the read_file() function in apport/hookutils.py.

Understanding CVE-2021-20657

This section will delve into the details surrounding the CVE, including its impact and technical aspects.

What is CVE-2021-20657?

The vulnerability in the 'apport' package, specifically in the read_file() function of apport/hookutils.py, fails to properly handle symbolic links or FIFOs. This oversight enables malicious actors to access confidential information when the function is utilized by the xorg package apport hooks.

The Impact of CVE-2021-20657

With a CVSS base score of 7.3, this vulnerability poses a high risk, primarily impacting confidentiality. It has a low attack complexity and can be exploited by local attackers, potentially leading to the exposure of private data to unauthorized users.

Technical Details of CVE-2021-20657

This section will outline the technical specifics of the CVE, including the vulnerability description, affected systems, and the exploitation mechanism.

Vulnerability Description

The vulnerability arises from the improper handling of symbolic links and FIFOs in the read_file() function of apport/hookutils.py, allowing unauthorized access to private data.

Affected Systems and Versions

The 'apport' versions affected by this CVE include 2.20.1, 2.20.9, 2.20.11-0ubuntu27, 2.20.11-0ubuntu50, and 2.20.11-0ubuntu65, among others.

Exploitation Mechanism

Local attackers can exploit this vulnerability by manipulating symbolic links or FIFOs, gaining unauthorized access to sensitive information stored in the xorg package's apport hooks.

Mitigation and Prevention

To safeguard systems against CVE-2021-20657, immediate steps need to be taken along with the implementation of long-term security practices and timely patching.

Immediate Steps to Take

It is recommended to update the 'apport' package to a non-vulnerable version immediately. Additionally, restrict access to sensitive data and monitor file system activities.

Long-Term Security Practices

Implement strict file access permissions, conduct regular security audits, and educate users about secure file handling practices to prevent similar vulnerabilities.

Patching and Updates

Stay informed about security updates from Canonical and promptly apply patches to eliminate vulnerabilities and enhance system security.