CVE-2026-72236 s390/perf_cpum_cf: Add missing array_index_nospec() to __hw_perf_event_init()
A missing speculation barrier in the Linux kernel s390 perf driver allows local attackers to potentially read sensitive memory via speculative execution.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72236?
CVE-2026-72236 is a vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
s390/perf_cpum_cf: Add missing array_index_nospec() to __hw_perf_event_init()
ev variable is userspace controlled via event->attr.config and used as an array index after bounds checking, but without speculation barriers.
Add the missing array_index_nospec() call to prevent speculative execution.
Which versions are affected by CVE-2026-72236?
How do I fix CVE-2026-72236?
Apply the vendor's patch.
Is CVE-2026-72236 being exploited?
There is no known exploitation of CVE-2026-72236 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72236, DEBIAN-CVE-2026-72236, GHSA-54pj-2wqr-j294, UBUNTU-CVE-2026-72236.