CVE-2016-6259

medium
Published 2016-08-02 · Modified 2026-05-06
CVSS v3
6.2
CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v2
4.9
VIR risk
6.2

Description

Xen 4.5.x through 4.7.x do not implement Supervisor Mode Access Prevention (SMAP) whitelisting in 32-bit exception and event delivery, which allows local 32-bit PV guest OS kernels to cause a denial of service (hypervisor and VM crash) by triggering a safety check.

Predictions

Exploit likelihood
62%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2016-6259

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — http://xenbits.xen.org/xsa/xsa183-unstable.patch

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — http://xenbits.xen.org/xsa/xsa183-4.6.patch

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — http://xenbits.xen.org/xsa/advisory-183.html

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — http://support.citrix.com/article/CTX214954

OS impact

OSVersionStatusFixed in
debian debianbookwormfixed4.8.0~rc3-1
debian debianbullseyefixed4.8.0~rc3-1
debian debianforkyfixed4.8.0~rc3-1
debian debiansidfixed4.8.0~rc3-1
debian debiantrixiefixed4.8.0~rc3-1

Application impact

VendorProductVersionsFixed
citrixxenserver6.0
citrixxenserver6.0.2
citrixxenserver6.1
citrixxenserver6.2.0
citrixxenserver6.5.0
citrixxenserver7.0

References

CWEs

CWE-20

Verify integrity in audit chain (admin only). AS-IS.