FreeBSD Security Advisory FreeBSD-SA-18:13.nfs
27 November, 2018 by firstname.lastname@example.org | freebsd
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-18:13.nfs Security Advisory The FreeBSD Project Topic: Multiple vulnerabilities in NFS server code Category: core Module: nfs Announced: 2018-11-27 Credits: Jakub Jirasek, Secunia Research at Flexera Affects: All supported versions of FreeBSD. Corrected: 2018-11-23 20:41:54 UTC (stable/11, 11.2-STABLE) 2018-11-27 19:42:16 UTC (releng/11.2, 11.2-RELEASE-p5) CVE Name: CVE-2018-17157, CVE-2018-17158, CVE-2018-17159 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 Network File System (NFS) allows a host to export some or all of its file systems so that other hosts can access them over the network and mount them as if they were local. FreeBSD includes both server and client implementations of NFS. II. Problem Description Insufficient and improper checking in the NFS server code could cause a denial of service or possibly remote code execution via a specially crafted network packet. III. Impact A remote attacker could cause the NFS server to crash, resulting in a denial of service, or possibly execute arbitrary code on the server. IV. Workaround No workaround is available, but systems that do not provide NFS services are not vulnerable. Additionally, it is highly recommended the NFS service port (default port number 2049) is protected via a host or network based firewall to prevent arbitrary, untrusted clients from being able to connect. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date. Afterward, reboot the system. 2) 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, reboot the system. 3) 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 11.2] # fetch https://security.FreeBSD.org/patches/SA-18:13/nfs.patch # fetch https://security.FreeBSD.org/patches/SA-18:13/nfs.patch.asc # gpg --verify nfs.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/11/ r340854 releng/11.2/ r341088 - ------------------------------------------------------------------------- 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://www.flexerasoftware.com/enterprise/company/about/secunia-research/> <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-17157> <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-17158> <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-17159> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-18:13.nfs.asc> -----BEGIN PGP SIGNATURE----- iQKTBAEBCgB9FiEE/A6HiuWv54gCjWNV05eS9J6n5cIFAlv9n85fFIAAAAAALgAo aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldEZD MEU4NzhBRTVBRkU3ODgwMjhENjM1NUQzOTc5MkY0OUVBN0U1QzIACgkQ05eS9J6n 5cKJEg//Umbe1QOUgV0Z6EsdlQffNMo9MHbAz75vCqeaibI36Ng9vmkLKGlS6nCA 5mKFS+BvM5CkekBaiQ6BR8t0xWsrFwX6JCUayQ2FsCSo4rwCZms3AIbvt68vjQAm xWuQIMJzYku5+kALtcXXvVkLhMCaioVDpZmuPCO+rY79OVM4xP1MsnTfqEZSNo+n Cz2urH4eO60YsM8w05coQ3hnOsUjTCk8yCh3+R/uYK1VouLDgD8q96T1eG2ozny6 vwEMK3AjmcpvFkTIF3/2I6TTA5K+Zd+nqzhzPM5HjbLZmdQV02NHcoGaZrK1wsQw D+3wf8icBMfLt9rTUbEqVdvg5FRDkTo8/dH1wY85gWZ2wsSgCqI2wRuqBH4bp3bb Gcf2+D4vgX6YY5cZ/wFDcYWpghhrmXUbgnH7PnyVfYB0Ufta9utgMOQKMS0mUWwM DlHP+fL/A8lhPvXIhl1DtSa/TQAiAdMG1JwktzThKrUzjL8bntmjoqtr1Xcp2txJ hgALulqz9nzkHaHcEolgk5xFTvx4gCzhjII7XEU3/rLNPPlJK3Pfo0UvPLAUkdLj McnKqOyQ6uSl8/lNuVsd3JCZ3dlsES7VmdEu0YJ4goc/6/AB8KXnSqzheT7Cjn1p lGzbFYmXosUj9NEQl/SOg6O8LnRrJIw4Tbm9vfkDss1G+sjUdaA= =m/Lh -----END PGP SIGNATURE----- _______________________________________________ email@example.com mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-announce To unsubscribe, send any mail to "firstname.lastname@example.org"