1. Forum
  2. Usenet
  3. COMP.UNIX.BSD.FREEBSD.ANN

  • [FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-18:14.bhyve

    From FreeBSD Security Advisories@21:1/5 to All on Tue Dec 4 20:00:00 2018
    -----BEGIN PGP SIGNED MESSAGE-----
    Hash: SHA512

    ============================================================================= FreeBSD-SA-18:14.bhyve Security Advisory
    The FreeBSD Project

    Topic: Insufficient bounds checking in bhyve(8) device model

    Category: core
    Module: bhyve
    Announced: 2018-12-04
    Credits: Reno Robert
    Affects: All supported versions of FreeBSD.
    Corrected: 2018-12-04 18:32:50 UTC (stable/11, 11.2-STABLE)
    2018-12-04 18:38:32 UTC (releng/11.2, 11.2-RELEASE-p6)
    CVE Name: CVE-2018-17160

    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 bhyve hypervisor uses the bhyve(8) program to emulate support for most virtual devices used by guest operating systems.

    II. Problem Description

    Insufficient bounds checking in one of the device models provided by bhyve(8) can permit a guest operating system to overwrite memory in the bhyve(8) processing possibly permitting arbitary code execution.

    III. Impact

    A guest OS using a firmware image can cause the bhyve process to crash, or possibly execute arbitrary code on the host as root.

    IV. Workaround

    The device model in question is only enabled when booting guests with a firmware image such as the UEFI images from the bhyve-firmware package.
    Guests booted using bhyveload(8) or grub2-bhyve are not affected. Guests
    using operating systems supported by bhyveload(8) or grub2-bhyve can be
    booted using these tools as a workaround.

    No workaround is available for guest operating systems such as Windows that require a firmware image.

    V. Solution

    Perform one of the following:

    Upgrade your vulnerable system to a supported FreeBSD stable or
    release / security branch (releng) dated after the correction date.

    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

    Afterward, restart guests using firmware images.

    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.

    # fetch https://security.FreeBSD.org/patches/SA-18:14/bhyve.patch
    # fetch https://security.FreeBSD.org/patches/SA-18:14/bhyve.patch.asc
    # gpg --verify bhyve.patch.asc

    b) Apply the patch. Execute the following commands as root:

    # cd /usr/src
    # patch < /path/to/patch

    c) Recompile the operating system using buildworld and installworld as described in <URL:https://www.FreeBSD.org/handbook/makeworld.html>.

    Afterward, restart guests using firmware images.

    VI. Correction details

    The following list contains the correction revision numbers for each
    affected branch.

    Branch/path Revision
    - ------------------------------------------------------------------------- stable/11/ r341486 releng/11.2/ r341488
    - -------------------------------------------------------------------------

    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://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-17160>

    The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-18:14.bhyve.asc> -----BEGIN PGP SIGNATURE-----

    iQKTBAEBCgB9FiEE/A6HiuWv54gCjWNV05eS9J6n5cIFAlwGykdfFIAAAAAALgAo aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldEZD MEU4NzhBRTVBRkU3ODgwMjhENjM1NUQzOTc5MkY0OUVBN0U1QzIACgkQ05eS9J6n 5cKcIQ/+Ktt7+SZPoWZQmJv6LdT6qI+na0+/9LDwBoC+Tj37heFUnhcMTxDDH4o3 nexELxF1xHmRchooRKfJr7npa8CF4jBzp2PSb+783q6TrFKe90ohlmt56lRB6gJg 3IJX5TxvAvLsqTgwPyALqyy3H5C8cY3btHPsZIArK0WVRTB74K3mr3L3IRVTcMCv 9cbUZyDO21ZIDTB5h9FYGo+6bg8hvZztmromkxssqlKKS8TUltGr/H3k6EHlnEA9 rG+6kswIgyeXNFrdksD6ni7L5Z3lwR/DFiU2d/lageQZ6vgDUa3c0KMhepfelfJR AiUtGpgfCDuHZ1NV2uyr9I6nPRHhdxPy3o2bF/B7+SLdn03tcZiO0tx3Wf68EQlt jAYFuup7+TFKoupsHlb2fkQxNOeQCr6dF+ikJDVgwCqmx2zn9tDo/tWoNdH+Jylx MDKsE369HOSRGR3Ua1ELEtOEzbGbcUHJyT6I1E2poctE61hYI+5te6pasY3ReN68 vyFMAo5ey0kJ6mi2YVcvDo2ZEb/GP1noJkdquYpIm8Ko0TPtivaMHXLIPcpLiJUc fBZexGCXJnb8f6ClMMU12U6f3H35Hz1AUPG3MSWHGgoczQBZJ8PECJ+r0X5bhkzW Ymlksu/HprW4tFLCdD4mB7lewvr3qpmoRoS1KwgMoXnRKzPbGsc=
    =4zGb
    -----END PGP SIGNATURE-----
    _______________________________________________
    freebsd-announce@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-announce
    To unsubscribe, send any mail to "freebsd-announce-unsubscribe@freebsd.org"

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)