CVE-2018-14611 Explained : Impact and Mitigation

A problem has been found in the Linux kernel up to version 4.17.10 where a use-after-free vulnerability occurs due to the absence of chunk type flag verifications in btrfs_check_chunk_valid in fs/btrfs/volumes.c.

Understanding CVE-2018-14611

This CVE entry highlights a critical vulnerability in the Linux kernel that could be exploited by mounting a manipulated btrfs image.

What is CVE-2018-14611?

This CVE describes a use-after-free vulnerability in the Linux kernel up to version 4.17.10 when handling crafted btrfs images.

The Impact of CVE-2018-14611

The vulnerability could allow an attacker to execute arbitrary code or cause a denial of service by mounting a malicious btrfs image.

Technical Details of CVE-2018-14611

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The issue arises from a lack of chunk type flag checks in btrfs_check_chunk_valid in fs/btrfs/volumes.c, leading to a use-after-free in try_merge_free_space() when mounting a manipulated btrfs image.

Affected Systems and Versions

Affected systems: Linux kernel up to version 4.17.10
Affected versions: Not applicable

Exploitation Mechanism

The vulnerability can be exploited by mounting a specifically crafted btrfs image, triggering the use-after-free condition in the affected function.

Mitigation and Prevention

Protecting systems from CVE-2018-14611 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply security updates provided by the Linux kernel maintainers promptly.
Avoid mounting untrusted or manipulated btrfs images.

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version.
Implement proper access controls and restrictions on mounting filesystems.

Patching and Updates

Ensure that the Linux kernel is regularly updated with the latest security patches to mitigate the risk of exploitation.