Improper access control in Linux kernel - CVE-2026-89984
Published: September 16, 2026
Vulnerability identifier: #VU150302
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-2026-89984
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to disclose kernel addresses.
The vulnerability exists due to improper privilege-level validation in the intel_pmu_lbr_filter() LBR stack filtering function when filtering sampled LBR entries for user-only branch stacks. A local user can request a user-only branch stack through perf to disclose kernel addresses.
The issue affects systems where architectural LBR lacks CPL filtering support.
Affected software
Linux kernel
How to mitigate CVE-2026-89984
Install security update from vendor's repository.
External References
- https://git.kernel.org/stable/c/3c492c8eba02698ca893a9a13388d2adf6dfb839
- https://git.kernel.org/stable/c/68c4b780b266a435261a1e029bede5ee3c2735cc
- https://git.kernel.org/stable/c/6ac26161db27f7fb9d9e89ae240dbe52795496cc
- https://git.kernel.org/stable/c/b589147f54adc62e4172e4acf079ad5fb7b3687f
- https://git.kernel.org/stable/c/be0628a101ac05b085aaa4f650d48bd3915e80fa
- https://git.kernel.org/stable/c/ca19a175e89b7de604fab736436cbab74030b47a
- https://git.kernel.org/stable/c/e2b0575900ff72aa82748af96e7bd564ade5157a
- https://git.kernel.org/stable/c/f3705db4e6378cc1b91a38ce0fe2f879055e23ca