CVE-2016-7777 Race condition in n/a

Medium 6.3 Published 7 Oct 2016 Updated 6 Aug 2024

Local guest users can read or modify FPU/MMX/XMM registers of other tasks by exploiting a race condition during instruction emulation.

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-2016-7777?

CVE-2016-7777 is a medium-severity vulnerability in Xen Xen, published on 7 Oct 2016. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Xen 4.7.x and earlier does not properly honor CR0.TS and CR0.EM, which allows local x86 HVM guest OS users to read or modify FPU, MMX, or XMM register state information belonging to arbitrary tasks on the guest by modifying an instruction while the hypervisor is preparing to emulate it.

Weakness: CWE-362

Which versions are affected by CVE-2016-7777?

It affects 1 product.

Products include Xen Xen.

How do I fix CVE-2016-7777?

Apply the vendor's patch.

Is CVE-2016-7777 being exploited?

There is no known exploitation of CVE-2016-7777 in the wild and no public exploit code.

All Xen Xen vulnerabilities

Sources

Also known as ALPINE-CVE-2016-7777, DEBIAN-CVE-2016-7777, DLA-699-1, GHSA-cr4c-368c-2fc2, UBUNTU-CVE-2016-7777.