SB2020112801 - Privilege escalation in __split_huge_pmd() in Linux kernel
Published: November 28, 2020 Updated: March 18, 2021
Security Bulletin ID
SB2020112801
Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Out-of-bounds write (CVE-ID: CVE-2020-29368)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing untrusted input within the __split_huge_pmd() function in mm/huge_memory.c in the Linux kernel. A local user can abuse the copy-on-write implementation and gain unintended write access because of a race condition in a THP mapcount check.
Remediation
Install update from vendor's website.