Description
The instruction decoder in arch/x86/kvm/emulate.c in the KVM subsystem in the Linux kernel before 3.18-rc2 does not properly handle invalid instructions, which allows guest OS users to cause a denial of service (NULL pointer dereference and host OS crash) via a crafted application that triggers (1) an improperly fetched instruction or (2) an instruction that occupies too many bytes. NOTE: this vulnerability exists because of an incomplete fix for CVE-2014-8480.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1156615
- https://github.com/torvalds/linux/commit/a430c9166312e1aa3d80bce32374233bdbfeba32
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=a430c9166312e1aa3d80bce32374233bdbfeba32
- 62042 third-party-advisory
- [oss-security] 20141023 CVE Request: Linux 3.17 guest-triggerable KVM OOPS mailing-list
- [kvm] 20141013 [PATCH 0/2] KVM: x86: Fixing clflush/hint_nop/prefetch mailing-list