Description
The access_pmu_evcntr function in arch/arm64/kvm/sys_regs.c in the Linux kernel before 4.8.11 allows privileged KVM guest OS users to cause a denial of service (assertion failure and host OS crash) by accessing the Performance Monitors Cycle Count Register (PMCCNTR).
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | Linux kernel before 4.9 | Linux kernel before 4.9 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 4.8.11-1 | — |
| Debian 13 | linux | 4.8.11-1 | — |
| Debian 12 | linux | 4.8.11-1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | perf +15 | 4.11.0-44.el7a | RHEA-2017:3163 |
Advisories 1
- RHEA-2017:3163 Red Hat Enhancement Advisory: new packages: kernel-alt Red Hat Security Advisories (RHSA) · Jun 26, 2026
References
- https://github.com/torvalds/linux/commit/9e3f7a29694049edd728e2400ab57ad7553e5aa9
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.8.11
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=9e3f7a29694049edd728e2400ab57ad7553e5aa9
- https://bugzilla.redhat.com/show_bug.cgi?id=1492984