The Vigil@nce team watches public vulnerabilities impacting your computers, and then offers security solutions, a vigilance database and tools to fix them.

Vulnerability of Xen: denial of service via X86 HVM Context Switch Recursion

Synthesis of the vulnerability 

An attacker, inside a guest system, can trigger a fatal error via X86 HVM Context Switch Recursion of Xen, in order to trigger a denial of service on the host system.
Impacted systems: Debian, Fedora, openSUSE Leap, SUSE Linux Enterprise Desktop, SLES, Xen.
Severity of this alert: 1/4.
Creation date: 15/12/2020.
Références of this alert: CERTFR-2020-AVI-824, CVE-2020-29566, DSA-4812-1, FEDORA-2020-64859a826b, FEDORA-2020-df772b417b, openSUSE-SU-2020:2313-1, openSUSE-SU-2020:2331-1, SUSE-SU-2020:14578-1, SUSE-SU-2020:3880-1, SUSE-SU-2020:3881-1, SUSE-SU-2020:3913-1, SUSE-SU-2020:3914-1, SUSE-SU-2020:3915-1, SUSE-SU-2020:3916-1, SUSE-SU-2020:3945-1, VIGILANCE-VUL-34115, XSA-348.

Description of the vulnerability 

An attacker, inside a guest system, can trigger a fatal error via X86 HVM Context Switch Recursion of Xen, in order to trigger a denial of service on the host system.
Full bulletin, software filtering, emails, fixes, ... (Request your free trial)

This computer weakness announce impacts software or systems such as Debian, Fedora, openSUSE Leap, SUSE Linux Enterprise Desktop, SLES, Xen.

Our Vigil@nce team determined that the severity of this security alert is low.

The trust level is of type confirmed by the editor, with an origin of user shell.

An attacker with a expert ability can exploit this vulnerability.

Solutions for this threat 

Xen: patch for X86 HVM Context Switch Recursion.
A patch is available:
  http://xenbits.xen.org/xsa/xsa348-1.patch
  http://xenbits.xen.org/xsa/xsa348-2.patch
  http://xenbits.xen.org/xsa/xsa348-3.patch
  http://xenbits.xen.org/xsa/xsa348-4.10.patch
  http://xenbits.xen.org/xsa/xsa348-4.11.patch
  http://xenbits.xen.org/xsa/xsa348-4.12.patch
  http://xenbits.xen.org/xsa/xsa348-4.13-1.patch
  http://xenbits.xen.org/xsa/xsa348-4.13-2.patch
  http://xenbits.xen.org/xsa/xsa348-4.13-3.patch

Debian 10: new xen packages.
New packages are available:
  Debian 10: xen 4.11.4+57-g41a822c392-2

Fedora 32-33: new xen packages.
New packages are available:
  Fedora 32: xen 4.13.2-5.fc32
  Fedora 33: xen 4.14.0-14.fc33

openSUSE Leap 15.1: new xen packages.
New packages are available:
  openSUSE Leap 15.1: xen 4.12.4_06-lp151.2.36.1

openSUSE Leap 15.2: new xen packages.
New packages are available:
  openSUSE Leap 15.2: xen 4.13.2_06-lp152.2.21.1

SUSE LE 11 SP4: new xen packages.
New packages are available:
  SUSE LE 11 SP4: xen 4.4.4_48-61.61.1

SUSE LE 12 SP2: new xen packages.
New packages are available:
  SUSE LE 12 SP2: xen 4.7.6_14-43.73.1

SUSE LE 12 SP3: new xen packages.
New packages are available:
  SUSE LE 12 SP3: xen 4.9.4_16-3.80.1

SUSE LE 12 SP4: new xen packages.
New packages are available:
  SUSE LE 12 SP4: xen 4.11.4_16-2.48.1

SUSE LE 12 SP5: new xen packages.
New packages are available:
  SUSE LE 12 SP5: xen 4.12.4_06-3.36.1

SUSE LE 15 RTM: new xen packages.
New packages are available:
  SUSE LE 15 RTM: xen 4.10.4_24-3.53.1

SUSE LE 15 SP1: new xen packages.
New packages are available:
  SUSE LE 15 SP1: xen 4.12.4_06-3.40.1

SUSE LE 15 SP2: new xen packages.
New packages are available:
  SUSE LE 15 SP2: xen 4.13.2_06-3.22.1
Full bulletin, software filtering, emails, fixes, ... (Request your free trial)

Computer vulnerabilities tracking service 

Vigil@nce provides cybersecurity analysis. The Vigil@nce security watch publishes vulnerability bulletins about threats impacting the information system.