Bug 1313686 (CVE-2016-4020)

Summary: CVE-2016-4020 Qemu: i386: leakage of stack memory to guest in kvmvapic.c
Product: [Other] Security Response Reporter: Adam Mariš <amaris>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: abaron, ailan, alonbl, apevec, areis, bmcclain, carnil, chrisw, cvsbot-xmlrpc, dallan, dblechte, drjones, gkotton, imammedo, jen, jjoyce, jschluet, kbasil, knoel, lhh, lpeer, markmc, mgoldboi, michal.skrivanek, mkenneth, mrezanin, mst, pbonzini, ppandit, rbryant, rkrcmar, sclewis, security-response-team, slong, srevivo, tdecacqu, virt-maint, vkuznets, ykaul
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard: impact=low,public=20160407,reported=20160302,source=researcher,cvss2=2.9/AV:A/AC:M/Au:N/C:P/I:N/A:N,cvss3=3.4/CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N,cwe=CWE-200,rhel-5/kvm=notaffected,rhel-5/xen=notaffected,rhel-6/qemu-kvm=notaffected,rhel-7/qemu-kvm=affected,rhel-7/qemu-kvm-rhev=affected,openstack-5/qemu-kvm-rhev=wontfix,openstack-6/qemu-kvm-rhev=affected,openstack-7/qemu-kvm-rhev=affected,openstack-8/qemu-kvm-rhev=affected,fedora-all/qemu=affected,fedora-all/xen=notaffected,openstack-9/qemu-kvm-rhev=affected,openstack-10/qemu-kvm-rhev=affected,openstack-11/qemu-kvm-rhev=affected,openstack-12/qemu-kvm-rhev=notaffected
Fixed In Version: Doc Type: Bug Fix
Doc Text:
An information-exposure flaw was found in Quick Emulator (QEMU) in Task Priority Register (TPR) optimizations for 32-bit Windows guests. The flaw could occur while accessing TPR. A privileged user inside a guest could use this issue to read portions of the host memory.
Story Points: ---
Clone Of: Environment:
Last Closed: 2019-06-08 02:49:13 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On: 1326904, 1335751, 1335752, 1335753, 1335754, 1335755, 1335756, 1381794, 1475713, 1475714    
Bug Blocks: 1313687, 1377819    

Description Adam Mariš 2016-03-02 08:41:46 UTC
Qemu emulator built with the Task Priority Register(TPR) optimizations for 32-bit Windows guests, is vulnerable to a information leakage issue. It could
occur while accessing Task Priority Register(TPR).

A privileged user/process inside guest could use this issue to leak host memory bytes.

Upstream patch:
---------------
  -> https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html

Reference:
----------
  -> http://www.openwall.com/lists/oss-security/2016/04/14/3

Comment 1 Adam Mariš 2016-03-02 08:42:07 UTC
Acknowledgments:

Name: Donghai Zdh (Alibaba Inc.)

Comment 3 Prasad J Pandit 2016-04-13 18:03:48 UTC
Created qemu tracking bugs for this issue:

Affects: fedora-all [bug 1326904]

Comment 6 Fedora Update System 2016-05-29 17:47:11 UTC
qemu-2.6.0-3.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.

Comment 7 Fedora Update System 2016-05-31 02:51:10 UTC
qemu-2.4.1-10.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 8 Fedora Update System 2016-06-07 01:19:26 UTC
qemu-2.3.1-15.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.

Comment 20 Eric Christensen 2017-07-28 13:34:33 UTC
Statement:

This has been rated as having Moderate security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle:
https://access.redhat.com/support/policy/updates/errata/.

Comment 21 errata-xmlrpc 2017-08-01 17:51:48 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:1856 https://access.redhat.com/errata/RHSA-2017:1856

Comment 22 errata-xmlrpc 2017-08-02 00:55:22 UTC
This issue has been addressed in the following products:

  Red Hat OpenStack Platform 10.0 (Newton)
  Red Hat OpenStack Platform 11.0 (Ocata)
  Red Hat Enterprise Linux OpenStack Platform 6.0 (Juno) for RHEL 7
  Red Hat Enterprise Linux OpenStack Platform 7.0 (Kilo) for RHEL 7
  Red Hat OpenStack Platform 8.0 (Liberty)
  Red Hat OpenStack Platform 9.0 (Mitaka)

Via RHSA-2017:2408 https://access.redhat.com/errata/RHSA-2017:2408

Comment 23 errata-xmlrpc 2017-08-02 04:43:55 UTC
This issue has been addressed in the following products:

  RHEV 4.X RHEV-H and Agents for RHEL-7

Via RHSA-2017:2392 https://access.redhat.com/errata/RHSA-2017:2392