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: privilege escalation via Restartable PV Type Change

Synthesis of the vulnerability 

An attacker, inside a guest system, can bypass restrictions via Restartable PV Type Change of Xen, in order to escalate his privileges on the host system.
Impacted software: XenServer, Debian, Fedora, openSUSE Leap, SUSE Linux Enterprise Desktop, SLES, Xen.
Severity of this computer vulnerability: 2/4.
Creation date: 11/12/2019.
Références of this announce: CERTFR-2019-AVI-628, CERTFR-2019-AVI-630, CTX266932, CVE-2019-19580, DSA-4602-1, FEDORA-2019-2e12bd3a9a, openSUSE-SU-2020:0011-1, SUSE-SU-2019:3296-1, SUSE-SU-2019:3297-1, SUSE-SU-2019:3309-1, SUSE-SU-2019:3310-1, SUSE-SU-2019:3338-1, SUSE-SU-2020:0334-1, SUSE-SU-2020:0388-1, SUSE-SU-2020:1630-1, VIGILANCE-VUL-31126, XSA-310.

Description of the vulnerability 

An attacker, inside a guest system, can bypass restrictions via Restartable PV Type Change of Xen, in order to escalate his privileges on the host system.
Full bulletin, software filtering, emails, fixes, ... (Request your free trial)

This security alert impacts software or systems such as XenServer, Debian, Fedora, openSUSE Leap, SUSE Linux Enterprise Desktop, SLES, Xen.

Our Vigil@nce team determined that the severity of this security weakness is medium.

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

An attacker with a expert ability can exploit this security announce.

Solutions for this threat 

Xen: version 4.12.2.
The version 4.12.2 is fixed:
  http://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=refs/heads/stable-4.12
  https://xenproject.org/downloads/xen-project-archives/xen-project-4-12-series/xen-project-4-12-2/

Xen: version 4.11.3.
The version 4.11.3 is fixed:
  http://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=refs/heads/stable-4.11
  https://xenproject.org/downloads/xen-project-archives/xen-project-4-11-series/xen-project-4-11-3/

Xen: patch for Restartable PV Type Change.
A patch is available:
  http://xenbits.xen.org/xsa/xsa310-4.9/0001-x86-mm-Set-old_guest_table-when-destroying-vcpu-page.patch
  http://xenbits.xen.org/xsa/xsa310-4.9/0002-x86-mm-alloc-free_lN_table-Retain-partial_flags-on-E.patch
  http://xenbits.xen.org/xsa/xsa310-4.9/0003-x86-mm-relinquish_memory-Grab-an-extra-type-ref-when.patch
  http://xenbits.xen.org/xsa/xsa310/0001-x86-mm-Set-old_guest_table-when-destroying-vcpu-page.patch
  http://xenbits.xen.org/xsa/xsa310/0002-x86-mm-alloc-free_lN_table-Retain-partial_flags-on-E.patch
  http://xenbits.xen.org/xsa/xsa310/0003-x86-mm-relinquish_memory-Grab-an-extra-type-ref-when.patch

Citrix Hypervisor, XenServer: patch.
A patch is available:
  Citrix Hypervisor 8.0: CTX263620 - https://support.citrix.com/article/CTX263620
  Citrix XenServer 7.6: CTX263619 - https://support.citrix.com/article/CTX263619
  Citrix XenServer 7.1 LTSR CU2: CTX263618 - https://support.citrix.com/article/CTX263618
  Citrix XenServer 7.0: CTX263617 - https://support.citrix.com/article/CTX263617

Debian 9/10: new xen packages.
New packages are available:
  Debian 9: xen 4.8.5.final+shim4.10.4-1+deb9u12
  Debian 10: xen 4.11.3+24-g14b62ab3e5-1~deb10u1

Fedora 30: new xen packages.
New packages are available:
  Fedora 30: xen 4.11.3-2.fc30

openSUSE Leap 15.1: new xen packages.
New packages are available:
  openSUSE Leap 15.1: xen 4.12.1_06-lp151.2.9.1

SUSE LE 12 SP1: new xen packages.
New packages are available:
  SUSE LE 12 SP1: xen 4.5.5_28-22.64.1

SUSE LE 12 SP2: new xen packages.
New packages are available:
  SUSE LE 12 SP2: xen 4.7.6_06-43.59.1

SUSE LE 12 SP3: new xen packages (16/12/2019).
New packages are available:
  SUSE LE 12 SP3: xen 4.9.4_06-3.59.1

SUSE LE 12 SP3: new xen packages (17/06/2020).
New packages are available:
  SUSE LE 12 SP3: xen 4.9.4_06-3.62.1

SUSE LE 12 SP4: new xen packages (18/12/2019).
New packages are available:
  SUSE LE 12 SP4: xen 4.11.3_02-2.20.1

SUSE LE 12 SP5: new xen packages.
New packages are available:
  SUSE LE 12 SP5: xen 4.12.1_10-3.8.1

SUSE LE 15 RTM: new xen packages.
New packages are available:
  SUSE LE 15 RTM: xen 4.10.4_08-3.28.1

SUSE LE 15 SP1: new xen packages.
New packages are available:
  SUSE LE 15 SP1: xen 4.12.1_06-3.9.1
Full bulletin, software filtering, emails, fixes, ... (Request your free trial)

Computer vulnerabilities tracking service 

Vigil@nce provides computers vulnerabilities patches. The Vigil@nce computer vulnerability tracking service alerts your teams of vulnerabilities or threats impacting your information system.