Resource management error in Xen - CVE-2019-19583

Vulnerability details

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

An issue was discovered in Xen through 4.12.x allowing x86 HVM/PVH guest OS users to cause a denial of service (guest OS crash) because VMX VMEntry checks mishandle a certain case. Please see XSA-260 for background on the MovSS shadow. Please see XSA-156 for background on the need for #DB interception. The VMX VMEntry checks do not like the exact combination of state which occurs when #DB in intercepted, Single Stepping is active, and blocked by STI/MovSS is active, despite this being a legitimate state to be in. The resulting VMEntry failure is fatal to the guest. HVM/PVH guest userspace code may be able to crash the guest, resulting in a guest Denial of Service. All versions of Xen are affected. Only systems supporting VMX hardware virtual extensions (Intel, Cyrix, or Zhaoxin CPUs) are affected. Arm and AMD systems are unaffected. Only HVM/PVH guests are affected. PV guests cannot leverage the vulnerability.

Affected software

How to mitigate CVE-2019-19583

External References

• http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00011.html
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/34HBFTYNMQMWIO2GGK7DB6KV4M6R5YPV/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/D5R73AYE53QA32KTMHUVKCX6E52CIS43/
• https://seclists.org/bugtraq/2020/Jan/21
• https://security.gentoo.org/glsa/202003-56
• https://www.debian.org/security/2020/dsa-4602
• https://xenbits.xen.org/xsa/advisory-308.html

Related Security Bulletins

• Multiple vulnerabilities in Xen
• OpenSUSE Linux update for xen
• Resource management error in xen (Alpine package)
• Gentoo update for Xen
• Debian update for xen
• Fedora 31 update for xen
• Fedora 30 update for xen