CVE-2023-4813 : Security Advisory and Response

This CVE article provides detailed information about CVE-2023-4813, concerning a potential use-after-free vulnerability in the glibc library.

Understanding CVE-2023-4813

This section will cover the vulnerability's description, impact, technical details, affected systems, and mitigation strategies.

What is CVE-2023-4813?

CVE-2023-4813 is a flaw found in the glibc library. In specific scenarios, the gaih_inet function may utilize memory that has been freed, leading to an application crash. This vulnerability is exploitable when the getaddrinfo function is called, and the hosts database in /etc/nsswitch.conf is configured with SUCCESS=continue or SUCCESS=merge.

The Impact of CVE-2023-4813

The vulnerability can potentially cause an application crash, impacting the availability of the affected system. Attackers may exploit this issue to disrupt services or execute arbitrary code, leading to a denial of service situation.

Technical Details of CVE-2023-4813

This section provides a deeper insight into the vulnerability's technical aspects.

Vulnerability Description

The vulnerability arises in the gaih_inet function of the glibc library due to the misuse of freed memory, resulting in a crash scenario.

Affected Systems and Versions

Affected Products:
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 8.6 EUS
Red Hat Enterprise Linux 9
Red Hat Virtualization 4 for Red Hat Enterprise Linux 8
Fedora
Unaffected Versions:
glibc version 2.36
glibc version 2.28-225.el8_8.6
glibc version 2.28-189.8.el8_6
glibc version 2.34-60.el9_2.7

Exploitation Mechanism

The vulnerability can be exploited by manipulating the getaddrinfo function in conjunction with a specific hosts database configuration.

Mitigation and Prevention

Understanding how to mitigate and prevent this vulnerability is crucial to maintaining system security.

Immediate Steps to Take

Removing the "SUCCESS=continue" or "SUCCESS=merge" configurations from the /etc/nsswitch.conf hosts database can help mitigate the risk associated with this vulnerability.

Long-Term Security Practices

Regularly updating glibc versions and monitoring security advisories can help in identifying and addressing vulnerabilities promptly.

Patching and Updates

It is recommended to apply patches provided by the software vendors to address the vulnerability and enhance the security posture of the affected systems. Stay informed about security updates and follow best practices to safeguard systems from potential exploits.