SB2019120810 - Use-after-free in Linux kernel



SB2019120810 - Use-after-free in Linux kernel

Published: December 8, 2019 Updated: August 8, 2020

Security Bulletin ID SB2019120810
Severity
High
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Use-after-free (CVE-ID: CVE-2019-19448)

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

In the Linux kernel 5.0.21 and 5.3.11, mounting a crafted btrfs filesystem image, performing some operations, and then making a syncfs system call can lead to a use-after-free in try_merge_free_space in fs/btrfs/free-space-cache.c because the pointer to a left data structure can be the same as the pointer to a right data structure.


Remediation

Install update from vendor's website.