CVE-2020-15563

NameCVE-2020-15563
DescriptionAn issue was discovered in Xen through 4.13.x, allowing x86 HVM guest OS users to cause a hypervisor crash. An inverted conditional in x86 HVM guests' dirty video RAM tracking code allows such guests to make Xen de-reference a pointer guaranteed to point at unmapped space. A malicious or buggy HVM guest may cause the hypervisor to crash, resulting in Denial of Service (DoS) affecting the entire host. Xen versions from 4.8 onwards are affected. Xen versions 4.7 and earlier are not affected. Only x86 systems are affected. Arm systems are not affected. Only x86 HVM guests using shadow paging can leverage the vulnerability. In addition, there needs to be an entity actively monitoring a guest's video frame buffer (typically for display purposes) in order for such a guest to be able to leverage the vulnerability. x86 PV guests, as well as x86 HVM guests using hardware assisted paging (HAP), cannot leverage the vulnerability.
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)
ReferencesDSA-4723-1
NVD severitymedium

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
xen (PTS)stretch (security), stretch4.8.5.final+shim4.10.4-1+deb9u12vulnerable
buster4.11.4+99-g8bce4698f6-1fixed
buster (security)4.11.4+107-gef32c7afa2-1fixed
bullseye4.14.1+11-gb0b734a8b3-1fixed
sid4.14.2+25-gb6a8c4f72d-1fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
xensourcestretch(unfixed)end-of-life
xensourcebuster4.11.4+24-gddaaccbbab-1~deb10u1DSA-4723-1
xensource(unstable)4.11.4+24-gddaaccbbab-1

Notes

[stretch] - xen <end-of-life> (DSA 4602-1)
https://xenbits.xen.org/xsa/advisory-319.html

Search for package or bug name: Reporting problems