Use of Uninitialized Variable in Linux kernel - CVE-2026-90272
Published: September 18, 2026
Vulnerability identifier: #VU151216
CSH Severity: Low
CVSS v4: 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]
CVE-ID: CVE-2026-90272
CWE-ID: CWE-457
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
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.
Affected software
Linux kernel
How to mitigate CVE-2026-90272
Install security update from vendor's repository.