CVE-2019-19318 : Security Advisory and Response

A use-after-free vulnerability in the Linux kernel version 5.3.11 due to mounting a manipulated btrfs image twice.

Understanding CVE-2019-19318

This CVE involves a specific vulnerability in the Linux kernel version 5.3.11 that can be exploited under certain conditions.

What is CVE-2019-19318?

The vulnerability arises from mounting a manipulated btrfs image twice, leading to a use-after-free issue in the rwsem_down_write_slowpath function.

The Impact of CVE-2019-19318

The vulnerability allows an attacker to potentially execute arbitrary code or crash the system, posing a security risk to affected systems.

Technical Details of CVE-2019-19318

Details regarding the vulnerability, affected systems, and exploitation mechanisms.

Vulnerability Description

The use-after-free vulnerability occurs due to the rwsem_owner_flags function returning a pointer that has already been freed in kernel/locking/rwsem.c.

Affected Systems and Versions

Linux kernel version 5.3.11

Exploitation Mechanism

Mounting a manipulated btrfs image twice

Mitigation and Prevention

Measures to mitigate the impact of CVE-2019-19318 and prevent exploitation.

Immediate Steps to Take

Apply patches provided by the Linux kernel maintainers
Monitor official sources for updates and security advisories

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version
Implement secure coding practices and conduct security audits

Patching and Updates

Keep the Linux kernel up to date with the latest security patches