CVE-2023-5369 : Exploit Details and Defense Strategies

This CVE-2023-5369 was published on October 4, 2023, by FreeBSD. It involves a vulnerability in the copy_file_range system call in FreeBSD.

Understanding CVE-2023-5369

This CVE highlights a flaw that allowed sandboxed processes with limited capabilities on a file descriptor to read from or write to arbitrary locations within the file associated with that descriptor.

What is CVE-2023-5369?

The vulnerability in the copy_file_range system call in FreeBSD allowed sandboxed processes lacking the necessary CAP_SEEK capability to read or write data to unintended locations in a file.

The Impact of CVE-2023-5369

This incorrect privilege check could be exploited by malicious actors to bypass security mechanisms and potentially access sensitive information or manipulate data within files.

Technical Details of CVE-2023-5369

The vulnerability, categorized as CWE-273 (Improper Check for Dropped Privileges), arises due to the insufficient capability rights check in the copy_file_range system call.

Vulnerability Description

Before the correction, the copy_file_range system call only checked for CAP_READ and CAP_WRITE capabilities on input and output file descriptors, respectively, instead of requiring the CAP_SEEK capability when using an offset.

Affected Systems and Versions

The affected product is FreeBSD, specifically version 13.2-RELEASE with modules related to capsicum.

Exploitation Mechanism

By exploiting this vulnerability, sandboxed processes with restricted capabilities on file descriptors could manipulate data within files, potentially leading to unauthorized access or data corruption.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-5369, it is crucial to take immediate steps, implement long-term security practices, and apply relevant patches and updates.

Immediate Steps to Take

Users are advised to update their FreeBSD systems to address this vulnerability promptly and restrict access to potentially impacted systems.

Long-Term Security Practices

Implementing the principle of least privilege, regularly monitoring for unusual activities, and educating users on secure coding practices can help prevent similar vulnerabilities in the future.

Patching and Updates

FreeBSD has released advisories and patches to address this vulnerability. Users should apply the provided patches and stay informed about security updates to protect their systems from potential exploits.