SB2021120824 - Privilege escalation in Linux kernel BPF subsystem 



SB2021120824 - Privilege escalation in Linux kernel BPF subsystem

Published: December 8, 2021 Updated: March 9, 2022

Security Bulletin ID SB2021120824
Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Buffer overflow (CVE-ID: CVE-2018-25020)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error within the BPF subsystem in the Linux kernel in ernel/bpf/core.c and net/core/filter.c. The kernel mishandles situations with a long jump over an instruction sequence where inner instructions require substantial expansions into multiple BPF instructions. A local user can run a specially crafted program to trigger memory corruption and execute arbitrary code with elevated privileges.


Remediation

Install update from vendor's website.