CVE-2021-32547 : Vulnerability Insights and Analysis

A vulnerability in the apport package of versions less than 2.20.1-0ubuntu2.30+esm1, 2.20.9-0ubuntu7.24, 2.20.11-0ubuntu27.18, 2.20.11-0ubuntu50.7, 2.20.11-0ubuntu65.1, and 2.14.1-0ubuntu3.29+esm7 could allow local users to access private data.

Understanding CVE-2021-32547

This CVE involves the read_file() function in apport/hookutils.py that could follow maliciously crafted symbolic links or open FIFOs, potentially exposing sensitive information. The vulnerability was published on May 25, 2021.

What is CVE-2021-32547?

The vulnerability in the apport package could permit unauthorized disclosure of confidential data to local users by following symbolic links or opening FIFOs when used by the openjdk-lts package apport hooks.

The Impact of CVE-2021-32547

With a CVSS base score of 7.3, this high-severity vulnerability could lead to a significant compromise of data confidentiality for affected systems.

Technical Details of CVE-2021-32547

The vulnerability is categorized under two Common Weakness Enumerations (CWEs): CWE-59 for improper link resolution before file access and CWE-61 for UNIX symbolic link (symlink) following.

Vulnerability Description

The vulnerability arises from read_file() in apport/hookutils.py following symbolic links or opening FIFOs, potentially exposing sensitive data to unauthorized local users.

Affected Systems and Versions

The vulnerability affects versions of the apport package less than 2.20.1-0ubuntu2.30+esm1, 2.20.9-0ubuntu7.24, 2.20.11-0ubuntu27.18, 2.20.11-0ubuntu50.7, 2.20.11-0ubuntu65.1, and 2.14.1-0ubuntu3.29+esm7.

Exploitation Mechanism

An attacker could exploit this vulnerability by creating malicious symbolic links or FIFOs, manipulating the read_file() function to expose private data.

Mitigation and Prevention

Following the detection of CVE-2021-32547, immediate actions need to be taken to secure the affected systems and prevent potential unauthorized access or data disclosure.

Immediate Steps to Take

Users are advised to apply the necessary security patches provided by Canonical and update their apport packages to versions that address this vulnerability.

Long-Term Security Practices

Implementing secure coding practices, regular security audits, and staying informed about security updates can help prevent similar vulnerabilities in the future.

Patching and Updates

Regularly monitor security advisories from Ubuntu and promptly apply patches to mitigate the risk of exploitation through vulnerabilities like CVE-2021-32547.