SB20260918403 - Use of Uninitialized Variable in Linux kernel perf driver
Published: September 18, 2026
Security Bulletin ID
SB20260918403
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use of Uninitialized Variable (CVE-ID: CVE-2026-90272)
CWE-ID: CWE-457 - Use of Uninitialized Variable
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to disclose uninitialized kernel memory.
The vulnerability exists due to use of uninitialized memory in the arm_pmuv3 BRBE branch stack handling when collecting branch records with PERF_SAMPLE_BRANCH_HW_INDEX. A local user can request branch records containing an unset hw_id value to disclose uninitialized kernel memory.
Remediation
Install update from vendor's website.