SB20240620142 - Observable discrepancy in Linux kernel



SB20240620142 - Observable discrepancy in Linux kernel

Published: June 20, 2024

Security Bulletin ID SB20240620142
Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Adjecent network
Highest impact Information disclosure

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Observable discrepancy (CVE-ID: CVE-2024-0564)

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

A flaw was found in the Linux kernel's memory deduplication mechanism. The max page sharing of Kernel Samepage Merging (KSM), added in Linux kernel version 4.4.0-96.119, can create a side channel. When the attacker and the victim share the same host and the default setting of KSM is 'max page sharing=256', it is possible for the attacker to time the unmap to merge with the victim's page. The unmapping time depends on whether it merges with the victim's page and additional physical pages are created beyond the KSM's 'max page share'. Through these operations, the attacker can leak the victim's page.


Remediation

Install update from vendor's website.