CVE-2018-12892

Upstream information

CVE-2018-12892 at MITRE

Description

An issue was discovered in Xen 4.7 through 4.10.x. libxl fails to pass the readonly flag to qemu when setting up a SCSI disk, due to what was probably an erroneous merge conflict resolution. Malicious guest administrators or (in some situations) users may be able to write to supposedly read-only disk images. Only emulated SCSI disks (specified as "sd" in the libxl disk configuration, or an equivalent) are affected. IDE disks ("hd") are not affected (because attempts to make them readonly are rejected). Additionally, CDROM devices (that is, devices specified to be presented to the guest as CDROMs, regardless of the nature of the backing storage on the host) are not affected; they are always read only. Only systems using qemu-xen (rather than qemu-xen-traditional) as the device model version are vulnerable. Only systems using libxl or libxl-based toolstacks are vulnerable. (This includes xl, and libvirt with the libxl driver.) The vulnerability is present in Xen versions 4.7 and later. (In earlier versions, provided that the patch for XSA-142 has been applied, attempts to create read only disks are rejected.) If the host and guest together usually support PVHVM, the issue is exploitable only if the malicious guest administrator has control of the guest kernel or guest kernel command line.

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having important severity.

CVSS v2 Scores
	National Vulnerability Database
Base Score	6.5
Vector	AV:N/AC:L/Au:S/C:P/I:P/A:P
Access Vector	Network
Access Complexity	Low
Authentication	Single
Confidentiality Impact	Partial
Integrity Impact	Partial
Availability Impact	Partial

CVSS v3 Scores
	SUSE
Base Score	5.5
Vector	AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Access Vector	Local
Access Complexity	Low
Privileges Required	Low
User Interaction	None
Scope	Unchanged
Confidentiality Impact	None
Integrity Impact	High
Availability Impact	None

SUSE Bugzilla entry: 1097523 [RESOLVED / FIXED]

SUSE Security Advisories:

SUSE-SU-2018:1981-1, published Tue Jul 17 13:07:52 MDT 2018
SUSE-SU-2018:2059-1, published Wed Jul 25 07:14:04 MDT 2018
SUSE-SU-2018:2081-1, published Fri Jul 27 10:07:58 MDT 2018
SUSE-SU-2018:2081-2, published Thu Oct 18 12:06:57 MDT 2018
openSUSE-SU-2018:2116-1, published Sat, 28 Jul 2018 15:07:34 +0200 (CEST)
openSUSE-SU-2018:2211-1, published Mon, 6 Aug 2018 15:12:23 +0200 (CEST)

List of released packages

Product(s)	Fixed package version(s)	References
SUSE CaaS Platform ALL	`xen >= 4.9.2_08-3.35.2` `xen-libs >= 4.9.2_08-3.35.2` `xen-tools-domU >= 4.9.2_08-3.35.2`	Patchnames: SUSE-CAASP-ALL-2018-1388
SUSE Enterprise Storage 4	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-Storage-4-2018-1414
SUSE Linux Enterprise Desktop 12 SP3	`xen >= 4.9.2_08-3.35.2` `xen-libs >= 4.9.2_08-3.35.2` `xen-libs-32bit >= 4.9.2_08-3.35.2`	Patchnames: SUSE-SLE-DESKTOP-12-SP3-2018-1388
SUSE Linux Enterprise Module for Basesystem 15	`xen >= 4.10.1_06-3.3.1` `xen-libs >= 4.10.1_06-3.3.1` `xen-tools-domU >= 4.10.1_06-3.3.1`	Patchnames: SUSE-SLE-Module-Basesystem-15-2018-1342
SUSE Linux Enterprise Module for Server Applications 15	`xen >= 4.10.1_06-3.3.1` `xen-devel >= 4.10.1_06-3.3.1` `xen-tools >= 4.10.1_06-3.3.1`	Patchnames: SUSE-SLE-Module-Server-Applications-15-2018-1342
SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-POS-12-SP2-CLIENT-2018-1414
SUSE Linux Enterprise Server 12 SP2-BCL	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SERVER-12-SP2-BCL-2018-1414
SUSE Linux Enterprise Server 12 SP2-ESPOS	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SERVER-12-SP2-ESPOS-2018-1414
SUSE Linux Enterprise Server 12 SP2-LTSS	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SERVER-12-SP2-2018-1414
SUSE Linux Enterprise Server 12 SP3	`xen >= 4.9.2_08-3.35.2` `xen-doc-html >= 4.9.2_08-3.35.2` `xen-libs >= 4.9.2_08-3.35.2` `xen-libs-32bit >= 4.9.2_08-3.35.2` `xen-tools >= 4.9.2_08-3.35.2` `xen-tools-domU >= 4.9.2_08-3.35.2`	Patchnames: SUSE-SLE-SERVER-12-SP3-2018-1388
SUSE Linux Enterprise Server for SAP Applications 12 SP2	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SAP-12-SP2-2018-1414
SUSE Linux Enterprise Server for SAP Applications 12 SP2-BCL	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SERVER-12-SP2-BCL-2018-1414
SUSE Linux Enterprise Server for SAP Applications 12 SP2-ESPOS	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SERVER-12-SP2-ESPOS-2018-1414
SUSE Linux Enterprise Server for SAP Applications 12 SP2-LTSS	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-SLE-SERVER-12-SP2-2018-1414
SUSE Linux Enterprise Server for SAP Applications 12 SP3	`xen >= 4.9.2_08-3.35.2` `xen-doc-html >= 4.9.2_08-3.35.2` `xen-libs >= 4.9.2_08-3.35.2` `xen-libs-32bit >= 4.9.2_08-3.35.2` `xen-tools >= 4.9.2_08-3.35.2` `xen-tools-domU >= 4.9.2_08-3.35.2`	Patchnames: SUSE-SLE-SERVER-12-SP3-2018-1388
SUSE Linux Enterprise Software Development Kit 12 SP3	`xen >= 4.9.2_08-3.35.2` `xen-devel >= 4.9.2_08-3.35.2`	Patchnames: SUSE-SLE-SDK-12-SP3-2018-1388
SUSE OpenStack Cloud 7	`xen >= 4.7.6_02-43.36.1` `xen-doc-html >= 4.7.6_02-43.36.1` `xen-libs >= 4.7.6_02-43.36.1` `xen-libs-32bit >= 4.7.6_02-43.36.1` `xen-tools >= 4.7.6_02-43.36.1` `xen-tools-domU >= 4.7.6_02-43.36.1`	Patchnames: SUSE-OpenStack-Cloud-7-2018-1414
openSUSE Leap 15.0	`xen >= 4.10.1_06-lp150.2.6.1` `xen-debugsource >= 4.10.1_06-lp150.2.6.1` `xen-devel >= 4.10.1_06-lp150.2.6.1` `xen-doc-html >= 4.10.1_06-lp150.2.6.1` `xen-libs >= 4.10.1_06-lp150.2.6.1` `xen-libs-32bit >= 4.10.1_06-lp150.2.6.1` `xen-libs-32bit-debuginfo >= 4.10.1_06-lp150.2.6.1` `xen-libs-debuginfo >= 4.10.1_06-lp150.2.6.1` `xen-tools >= 4.10.1_06-lp150.2.6.1` `xen-tools-debuginfo >= 4.10.1_06-lp150.2.6.1` `xen-tools-domU >= 4.10.1_06-lp150.2.6.1` `xen-tools-domU-debuginfo >= 4.10.1_06-lp150.2.6.1`	Patchnames: openSUSE-2018-766
openSUSE Leap 42.3	`xen >= 4.9.2_08-25.2` `xen-debugsource >= 4.9.2_08-25.2` `xen-devel >= 4.9.2_08-25.2` `xen-doc-html >= 4.9.2_08-25.2` `xen-libs >= 4.9.2_08-25.2` `xen-libs-debuginfo >= 4.9.2_08-25.2` `xen-tools >= 4.9.2_08-25.2` `xen-tools-debuginfo >= 4.9.2_08-25.2` `xen-tools-domU >= 4.9.2_08-25.2` `xen-tools-domU-debuginfo >= 4.9.2_08-25.2`	Patchnames: openSUSE-2018-803

Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification.

Product(s)	Source package	State
CaaS Platform 2.0	xen	Released
SUSE Linux Enterprise Desktop 12 SP3	xen	Released
SUSE Linux Enterprise Module for Basesystem 15 GA	xen	Released
SUSE Linux Enterprise Module for Server Applications 15 GA	xen	Released
SUSE Linux Enterprise SDK 11 SP4	xen	Not affected
SUSE Linux Enterprise SDK 12 SP3	xen	Released
SUSE Linux Enterprise Server 11 SP4	xen	Not affected
SUSE Linux Enterprise Server 12 SP2 LTSS	xen	Released
SUSE Linux Enterprise Server 12 SP3	xen	Released
SUSE Linux Enterprise Server for SAP Applications 12 SP2	xen	Released