Description
KVM in the Linux kernel before 4.8.12, when I/O APIC is enabled, does not properly restrict the VCPU index, which allows guest OS users to gain host OS privileges or cause a denial of service (out-of-bounds array access and host OS crash) via a crafted interrupt request, related to arch/x86/kvm/ioapic.c and arch/x86/kvm/ioapic.h.
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 | 4.8.15-1 | — |
| Debian 13 | linux | 4.8.15-1 | — |
| Debian 12 | linux | 4.8.15-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe | 4.8.0-39.42~16.04.1 | — |
References
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.8.12
- https://bugzilla.redhat.com/show_bug.cgi?id=1400804
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=81cdb259fb6d8c1c4ecfeea389ff5a73c07f5755
- 94640 vdb-entry
- https://github.com/torvalds/linux/commit/81cdb259fb6d8c1c4ecfeea389ff5a73c07f5755
- [oss-security] 20161202 CVE request: Kernel: kvm: out of bounds memory access via vcpu_id mailing-list