Bugzilla – Bug 895802
VUL-0: CVE-2014-7156: xen: XSA-106: Missing privilege level checks in x86 emulation of software interrupts
Last modified: 2015-02-10 10:50:01 UTC
embargoed, via pre-advisory mail Xen Security Advisory XSA-106 Missing privilege level checks in x86 emulation of software interrupts *** EMBARGOED UNTIL 2014-09-23 12:00 UTC *** ISSUE DESCRIPTION ================= The emulation of instructions which generate software interrupts fails to perform supervisor mode permission checks. However these instructions are not usually handled by the emulator. Exceptions to this are - - when a memory operand (implicit for the affected instructions) lives in (emulated or passed through) memory mapped IO space, - - in the case of guests running in 32-bit PAE mode, when such an instruction is (in execution flow) within four instructions of one doing a page table update, - - when an Invalid Opcode exception gets raised by a guest instruction, and the guest then (likely maliciously) alters the instruction to become one of the affected ones, - - when the guest is in real mode (in which case there are no privilege checks anyway). IMPACT ====== Malicious HVM guest user mode code may be able to crash the guest. VULNERABLE SYSTEMS ================== Xen versions from 3.3 onwards are vulnerable. Only user processes in HVM guests can take advantage of this vulnerability. MITIGATION ========== Running only PV guests will avoid this issue. There is no mitigation available for HVM guests. RESOLUTION ========== Applying the attached patch resolves this issue. xsa106.patch xen-unstable, Xen 4.4.x, Xen 4.3.x, Xen 4.2.x $ sha256sum xsa106*.patch 004051a839851d779de79b7804c5ef9a4d290bf2c8724b57299ca3a7b5a6173a xsa106.patch $
Created attachment 605561 [details] xsa106.patch attached patch
Affected packages: SLE-10-SP3-TERADATA: xen SLE-11-SP1-TERADATA: xen SLE-11-SP3: xen SLE-11-SP3-PRODUCTS: xen SLE-11-SP3-UPTU: xen
bugbot adjusting priority
Xen submitted for relevant SLE platforms.
is public
CVE-2014-7156
openSUSE-SU-2014:1279-1: An update that solves 10 vulnerabilities and has 8 fixes is now available. Category: security (important) Bug References: 798770,820873,833483,842006,858178,862608,864801,865682,867910,878841,880751,881900,891539,895798,895799,895802,896023,897657 CVE References: CVE-2013-4344,CVE-2013-4540,CVE-2014-2599,CVE-2014-3967,CVE-2014-3968,CVE-2014-4021,CVE-2014-7154,CVE-2014-7155,CVE-2014-7156,CVE-2014-7188 Sources used: openSUSE 12.3 (src): xen-4.2.4_04-1.32.1
openSUSE-SU-2014:1281-1: An update that solves 10 vulnerabilities and has four fixes is now available. Category: security (important) Bug References: 798770,820873,842006,864801,865682,875668,878841,880751,882127,895798,895799,895802,896023,897657 CVE References: CVE-2013-4344,CVE-2013-4540,CVE-2014-3124,CVE-2014-3967,CVE-2014-3968,CVE-2014-4021,CVE-2014-7154,CVE-2014-7155,CVE-2014-7156,CVE-2014-7188 Sources used: openSUSE 13.1 (src): xen-4.3.2_02-27.1
SUSE-SU-2014:1318-1: An update that solves 10 vulnerabilities and has 7 fixes is now available. Category: security (moderate) Bug References: 798770,833483,842006,858178,862608,864801,865682,867910,878841,880751,881900,882092,891539,895798,895799,895802,897657 CVE References: CVE-2013-4344,CVE-2013-4540,CVE-2014-2599,CVE-2014-3967,CVE-2014-3968,CVE-2014-4021,CVE-2014-7154,CVE-2014-7155,CVE-2014-7156,CVE-2014-7188 Sources used: SUSE Linux Enterprise Software Development Kit 11 SP3 (src): xen-4.2.4_04-0.9.1 SUSE Linux Enterprise Server 11 SP3 (src): xen-4.2.4_04-0.9.1 SUSE Linux Enterprise Desktop 11 SP3 (src): xen-4.2.4_04-0.9.1
SUSE-SU-2014:1710-1: An update that solves 13 vulnerabilities and has two fixes is now available. Category: security (moderate) Bug References: 826717,867910,875668,880751,895798,895799,895802,897657,901317,903850,903967,903970,905465,905467,906439 CVE References: CVE-2013-3495,CVE-2014-2599,CVE-2014-3124,CVE-2014-4021,CVE-2014-7154,CVE-2014-7155,CVE-2014-7156,CVE-2014-7188,CVE-2014-8594,CVE-2014-8595,CVE-2014-8866,CVE-2014-8867,CVE-2014-9030 Sources used: SUSE Linux Enterprise Server 11 SP2 LTSS (src): xen-4.1.6_08-0.5.1
SUSE-SU-2014:1732-1: An update that fixes 9 vulnerabilities is now available. Category: security (moderate) Bug References: 826717,880751,895798,895799,895802,903967,903970,905467,906439 CVE References: CVE-2013-3495,CVE-2014-4021,CVE-2014-7154,CVE-2014-7155,CVE-2014-7156,CVE-2014-8594,CVE-2014-8595,CVE-2014-8867,CVE-2014-9030 Sources used: SUSE Linux Enterprise Server 11 SP1 LTSS (src): xen-4.0.3_21548_18-0.9.1
SLE12 was fixed before GA