Is CVE-2016-10024 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2016-10024 being exploited in the wild.

How severe is CVE-2016-10024?

Medium severity, with a CVSS score of 6, published 26 January 2017.

Which products and versions are affected?

Citrix Xenserver 6.0.2, 6.2.0, 6.5, 7.0; Xen Project Xen through 4.8.x.

Is there a fix for CVE-2016-10024?

A patch was published on 2016-12-21: Patches released for Xen unstable and stable branches Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2016-10024 attacked?

It is attacked with local access, in an operating system.

Am I affected by CVE-2016-10024?

Check whether you run Citrix Xenserver or Xen Project Xen at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2016-10024: Xen denial of service via instruction stream modification in x86 PV guests

CVE-2016-10024 · Severity: medium · CVSS 6 · Published 2017-01-26

Xen is a hypervisor used to run multiple virtual machines on a single physical server. A vulnerability in how it handles certain guest operations allows a malicious administrator of a virtual machine to crash or freeze the entire physical host. This results in a total service outage for all other virtual machines running on that same hardware.

Technologies: Citrix Xenserver, Xen Project Xen. Vendors: Citrix, Xen Project.

Quick answers

Is CVE-2016-10024 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2016-10024 being exploited in the wild.
How severe is CVE-2016-10024?: Medium severity, with a CVSS score of 6, published 26 January 2017.
Which products and versions are affected?: Citrix Xenserver 6.0.2, 6.2.0, 6.5, 7.0; Xen Project Xen through 4.8.x.
Is there a fix for CVE-2016-10024?: A patch was published on 2016-12-21: Patches released for Xen unstable and stable branches Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2016-10024 attacked?: It is attacked with local access, in an operating system.
Am I affected by CVE-2016-10024?: Check whether you run Citrix Xenserver or Xen Project Xen at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A vulnerability exists in Xen's x86 instruction emulator when handling Paravirtualized (PV) guest operations, such as page table writes. A malicious guest kernel administrator can asynchronously modify the instruction stream during emulation to manipulate the EFLAGS.IF bit. This allows the guest to mask interrupts in a way that the hypervisor does not expect, leading to a host-level hang or crash (Denial of Service). The issue specifically affects x86 PV guests; HVM and ARM guests are not impacted. Patches have been released by the Xen Project (XSA-202) and various downstream vendors like Citrix and Debian.

Affected products

Xen Project Xen through 4.8.x
Citrix XenServer 6.0.2, 6.2.0, 6.5, 7.0

Timeline

2016-12-21: advisory: Xen Project released XSA-202
2016-12-21: patched: Patches released for Xen unstable and stable branches
2017-01-26: disclosed: NVD publication date

References

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