Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2019.4359 Machine Check Exception on Page Size Change 18 November 2019 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: mcepsc Publisher: FreeBSD Operating System: FreeBSD Impact/Access: Denial of Service -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2018-12207 Reference: ESB-2019.4288 ESB-2019.4271 ESB-2019.4254 Original Bulletin: https://security.freebsd.org/advisories/FreeBSD-SA-19:25.mcepsc.asc - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-19:25.mcepsc Security Advisory The FreeBSD Project Topic: Machine Check Exception on Page Size Change Category: core Module: kernel Announced: 2019-11-12 Credits: Intel Affects: All supported versions of FreeBSD. Corrected: 2019-11-12 18:03:26 UTC (stable/12, 12.1-STABLE) 2019-11-12 18:13:04 UTC (releng/12.1, 12.1-RELEASE-p1) 2019-11-12 18:13:04 UTC (releng/12.0, 12.0-RELEASE-p12) 2019-11-12 18:04:28 UTC (stable/11, 11.3-STABLE) 2019-11-12 18:13:04 UTC (releng/11.3, 11.3-RELEASE-p5) CVE Name: CVE-2018-12207 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:https://security.FreeBSD.org/>. I. Background The Intel machine check architecture is a mechanism to detect and report hardware errors, such as system bus errors, ECC errors, parity errors, and others. This allows the processor to signal the detection of a machine check error to the operating system. II. Problem Description Intel discovered a previously published erratum on some Intel platforms can be exploited by malicious software to potentially cause a denial of service by triggering a machine check that will crash or hang the system. III. Impact Malicious guest operating systems may be able to crash the host. IV. Workaround No workaround is available. Systems not running untrusted guest virtual machines are not impacted. V. Solution Upgrade your vulnerable system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date, and reboot. Perform one of the following: 1) To update your vulnerable system via a binary patch: Systems running a RELEASE version of FreeBSD on the i386 or amd64 platforms can be updated via the freebsd-update(8) utility: # freebsd-update fetch # freebsd-update install # shutdown -r +10min "Rebooting for a security update" 2) To update your vulnerable system via a source code patch: The following patches have been verified to apply to the applicable FreeBSD release branches. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. [FreeBSD 12.1] # fetch https://security.FreeBSD.org/patches/SA-19:25/mcepsc.12.1.patch # fetch https://security.FreeBSD.org/patches/SA-19:25/mcepsc.12.1.patch.asc # gpg --verify mcepsc.12.1.patch.asc [FreeBSD 12.0] # fetch https://security.FreeBSD.org/patches/SA-19:25/mcepsc.12.0.patch # fetch https://security.FreeBSD.org/patches/SA-19:25/mcepsc.12.0.patch.asc # gpg --verify mcepsc.12.0.patch.asc [FreeBSD 11.3] # fetch https://security.FreeBSD.org/patches/SA-19:25/mcepsc.11.patch # fetch https://security.FreeBSD.org/patches/SA-19:25/mcepsc.11.patch.asc # gpg --verify mcepsc.11.patch.asc b) Apply the patch. Execute the following commands as root: # cd /usr/src # patch < /path/to/patch c) Recompile your kernel as described in <URL:https://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the system. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - - ------------------------------------------------------------------------- stable/12/ r354650 releng/12.1/ r354653 releng/12.0/ r354653 stable/11/ r354651 releng/11.3/ r354653 - - ------------------------------------------------------------------------- To see which files were modified by a particular revision, run the following command, replacing NNNNNN with the revision number, on a machine with Subversion installed: # svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base Or visit the following URL, replacing NNNNNN with the revision number: <URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN> VII. References <URL:https://software.intel.com/security-software-guidance/software-guidance/machine-check-error-avoidance-page-size-change> <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-12207> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-19:25.mcepsc.asc> - -----BEGIN PGP SIGNATURE----- iQKTBAEBCgB9FiEE/A6HiuWv54gCjWNV05eS9J6n5cIFAl3K+khfFIAAAAAALgAo aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldEZD MEU4NzhBRTVBRkU3ODgwMjhENjM1NUQzOTc5MkY0OUVBN0U1QzIACgkQ05eS9J6n 5cIWdA//dTBwRIejd8vkgB/6wCLfXARU2Nw9je69JwfvpC/3BzkV+oD9rwoL7ltk NtOIu6otRmGnGHvC19WQ/JdlHUgtoxaxB26ROoU5BCYPJL7dU48T6l6RLbNXdMC4 MxU3mgbiDrVw9hhh42qKNVQ+ZzpMjgUPN1WRCyKQNlG7jNm5a8BvBaK0mFYkLdEw 9u+kNpXdaC9Ip45JI4QVS+jyK5JqFYWZw4SlB6AggcMO93QySzWWx4ZjXafw+0EK VoS8ByQ5nTlCVqq+hok+yVEz42mZ9AFSE1E1n3pe5TFZZmxF+NcDVMw324eLWUY3 pVX3S6Y0dCtKKvpyy2WIMrBV4Ro5BX3nQXJINdwCo2IlBRvJgK7u0wK3P0ionsJk Hc4x3sjZQm9Rhb8qqOh01wb7MjmGMWX/nlyishF6MAmnIV3dXctMaG00CSsIMbv9 jtx5v8uSGUHXb8bGYa6QLxaNN1gV6ZLMne1HLunkP7sCX9NYfibjkBXSIfNAkQTn MFrz9LLgy1K+8s2D1yFJZeyAZMWZ82yc14FSbux21pZS8MURpFt0OBYymAlzn0/J fhFEKg7rjKBuIBKjDycu9K8+s8h5TIGDROmgQojeqHm6wmlqyGVIPsREyBcCEvwM 16pasZC9s5C7aoSvzDExekR+LQOc8jVZ80KjNGmMga41tSANKTQ= =9nRn - -----END PGP SIGNATURE----- _______________________________________________ freebsd-security-notifications@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-security-notifications To unsubscribe, send any mail to "freebsd-security-notifications-unsubscribe@freebsd.org" - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBXdI2oGaOgq3Tt24GAQiW4w//ZnDAkb2osntaZLmer9P4AAUCWxURDEJF QtrMSW3h7kdN8G41FPqMBK8NfD6HZfRGfXujPVrr+biSAUKhNRSzuWVEdLPd1297 5XVZJ9xS+c5kXAd3vygeeP4WnuZiP8SRw8sqHq8iKsEBDM3THnmEmNJtWqeU42lq whSftow/fM2PEtuuzlxDtZMYLFRN3pEDPZQKl1/FESnMhYqvR9wUhg/lg1fplLYU gnLd2/6YcAWlZCHZaU08/qGcemxNh2/pENsOJTQi9U6Qndl/gs+J+Q1YUwuSX+MC EeAikDdAE6keTpWx47j8USQXwGst/TlUKeuapjnCvy6RLIg6B6ACHrbFPJvAov9L cEzJpbDLN+U42Pfl8m0nPd5/u2Y2I8dckg2BMkS1tvlWu75hlOQvuyOtD51o3eS5 ixqFgSBrFCDF948ND1Rqe5h99Mb+DmKE3slm5OxqiRaUTkfvIbXRaPlED72SFru4 iEvhgzkjoNZ4oCQP0X0OwIPq8MFYKBEtHfsm0XWJcibVno0lbsy8ub+u0F2zDyrB G1qFN65sbTdqr7RmudrRx8eB2nQE0CGa74b4E6NZFt1Yapot/+bLtRPc1AUGcIaD W5PgFWlrz99NZgDL3+eyGPBK7xrA2kXUmn+mqXWiBINGpv3M2SV3UdB2SsH7EfOd qQjDJejXX64= =p2mw -----END PGP SIGNATURE-----