Candidate: CVE-2019-19580
PublicDate: 2019-12-11 18:16:00 UTC
References:
 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-19580
 https://xenbits.xen.org/xsa/advisory-310.html
Description:
 An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS
 users to gain host OS privileges by leveraging race conditions in pagetable
 promotion and demotion operations, because of an incomplete fix for
 CVE-2019-18421. XSA-299 addressed several critical issues in restartable PV
 type change operations. Despite extensive testing and auditing, some corner
 cases were missed. A malicious PV guest administrator may be able to
 escalate their privilege to that of the host. All security-supported
 versions of Xen are vulnerable. Only x86 systems are affected. Arm systems
 are not affected. Only x86 PV guests can leverage the vulnerability. x86
 HVM and PVH guests cannot leverage the vulnerability. Note that these
 attacks require very precise timing, which may be difficult to exploit in
 practice.
Ubuntu-Description:
Notes:
 mdeslaur> hypervisor packages are in universe. For
 mdeslaur> issues in the hypervisor, add appropriate
 mdeslaur> tags to each section, ex:
 mdeslaur> Tags_xen: universe-binary
Mitigation:
Bugs:
Priority: medium
Discovered-by:
Assigned-to:
CVSS:
 nvd: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H [6.6 MEDIUM]

Patches_xen:
Tags_xen: universe-binary
upstream_xen: needs-triage
precise/esm_xen: DNE
trusty_xen: ignored (out of standard support)
trusty/esm_xen: DNE
xenial_xen: ignored (end of standard support, was needs-triage)
esm-infra/xenial_xen: needs-triage
bionic_xen: needs-triage
disco_xen: ignored (reached end-of-life)
eoan_xen: ignored (reached end-of-life)
focal_xen: not-affected (4.11.3+24-g14b62ab3e5-1ubuntu1)
groovy_xen: not-affected (4.11.3+24-g14b62ab3e5-1ubuntu1)
hirsute_xen: not-affected (4.11.3+24-g14b62ab3e5-1ubuntu1)
impish_xen: not-affected (4.11.3+24-g14b62ab3e5-1ubuntu1)
jammy_xen: not-affected (4.11.3+24-g14b62ab3e5-1ubuntu1)
devel_xen: not-affected (4.11.3+24-g14b62ab3e5-1ubuntu1)