Description
The create_pit_timer function in arch/x86/kvm/i8254.c in KVM 83, and possibly other versions, does not properly handle when Programmable Interval Timer (PIT) interrupt requests (IRQs) when a virtual interrupt controller (irqchip) is not available, which allows local users to cause a denial of service (NULL pointer dereference) by starting a timer.
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 6.0 | linux-2.6 | 2.6.32-39squeeze1 | DSA-2389-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | perf +15 | 2.6.32-220.7.1.el6 | RHSA-2012:0350 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Rhel Virtualization 5 | kvm +4 | 83-239.el5_7.1 | RHSA-2012:0051 |
Advisories 3
- RHSA-2012:0350 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2012:0051 Red Hat Security Advisory: kvm security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- DSA-2389-1 linux-2.6 - several Debian Security (DSA / DLA) · Mar 9, 2026
References
- RHSA-2012:0051 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=769721
- 51172 vdb-entry
- [oss-security] 20111221 Re: kernel: kvm: pit timer with no irqchip crashes the system mailing-list
- [kvm] 20111214 [PATCH 1/2] KVM: x86: Prevent starting PIT timers in the absence of irqchip support mailing-list
- SUSE-SU-2012:0616 vendor-advisory
- openSUSE-SU-2013:0925 vendor-advisory
- 1026559 vdb-entry