FreeBSD Security Advisories
2013-Apr-29 20:55 UTC
FreeBSD Security Advisory FreeBSD-SA-13:05.nfsserver
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
============================================================================FreeBSD-SA-13:05.nfsserver
Security Advisory
The FreeBSD Project
Topic: Insufficient input validation in the NFS server
Category: core
Module: nfsserver
Announced: 2013-04-29
Credits: Adam Nowacki
Affects: All supported versions of FreeBSD.
Corrected: 2013-04-29 20:15:43 UTC (stable/8, 8.4-PRERELEASE)
2013-04-29 20:15:47 UTC (releng/8.3, 8.3-RELEASE-p8)
2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC1-p1)
2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC2-p1)
2013-04-29 20:15:55 UTC (stable/9, 9.1-STABLE)
2013-04-29 20:16:00 UTC (releng/9.1, 9.1-RELEASE-p3)
CVE Name: CVE-2013-3266
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit <URL:http://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 on local disks. FreeBSD includes server and client
implementations of NFS.
FreeBSD 8.0 and onward has two NFS implementations: the original CSRG
NFSv2 and NFSv3 implementation and a new implementation which also
supports NFSv4.
FreeBSD 9.0 and onward uses the new NFS implementation by default.
II. Problem Description
When processing READDIR requests, the NFS server does not check that
it is in fact operating on a directory node. An attacker can use a
specially modified NFS client to submit a READDIR request on a file,
causing the underlying filesystem to interpret that file as a
directory.
III. Impact
The exact consequences of an attack depend on the amount of input
validation in the underlying filesystem:
- If the file resides on a UFS filesystem on a little-endian server,
an attacker can cause random heap corruption with completely
unpredictable consequences.
- If the file resides on a ZFS filesystem, an attacker can write
arbitrary data on the stack. It is believed, but has not been
confirmed, that this can be exploited to run arbitrary code in
kernel context.
Other filesystems may also be vulnerable.
IV. Workaround
Systems that do not provide NFS service are not vulnerable. Neither
are systems that do but use the old NFS implementation, which is the
default in FreeBSD 8.x.
To determine which implementation an NFS server is running, run the
following command:
# kldstat -v | grep -cw nfsd
This will print 1 if the system is running the new NFS implementation,
and 0 otherwise.
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.
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 http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch
# fetch http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch.asc
# gpg --verify nfsserver.patch.asc
b) Apply the patch.
# cd /usr/src
# patch < /path/to/patch
c) Recompile your kernel as described in
<URL:http://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the
system.
3) 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
VI. Correction details
The following list contains the revision numbers of each file that was
corrected in FreeBSD.
Branch/path Revision
- -------------------------------------------------------------------------
stable/8/ r250058
releng/8.3/ r250059
releng/8.4/ r250062
stable/9/ r250060
releng/9.1/ r250061
- -------------------------------------------------------------------------
VII. References
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3266
The latest revision of this advisory is available at
http://security.FreeBSD.org/advisories/FreeBSD-SA-13:05.nfsserver.asc
-----BEGIN PGP SIGNATURE-----
iEYEARECAAYFAlF+18oACgkQFdaIBMps37J1PACgm+zcbGd6xF1hkpvFVJbbwR0Q
9PoAnivbP1R0qXFyTlF/t3+sUYcxBtfQ
=polM
-----END PGP SIGNATURE-----
FreeBSD Security Advisories
2013-Apr-29 20:55 UTC
[FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-13:05.nfsserver
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
============================================================================FreeBSD-SA-13:05.nfsserver
Security Advisory
The FreeBSD Project
Topic: Insufficient input validation in the NFS server
Category: core
Module: nfsserver
Announced: 2013-04-29
Credits: Adam Nowacki
Affects: All supported versions of FreeBSD.
Corrected: 2013-04-29 20:15:43 UTC (stable/8, 8.4-PRERELEASE)
2013-04-29 20:15:47 UTC (releng/8.3, 8.3-RELEASE-p8)
2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC1-p1)
2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC2-p1)
2013-04-29 20:15:55 UTC (stable/9, 9.1-STABLE)
2013-04-29 20:16:00 UTC (releng/9.1, 9.1-RELEASE-p3)
CVE Name: CVE-2013-3266
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit <URL:http://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 on local disks. FreeBSD includes server and client
implementations of NFS.
FreeBSD 8.0 and onward has two NFS implementations: the original CSRG
NFSv2 and NFSv3 implementation and a new implementation which also
supports NFSv4.
FreeBSD 9.0 and onward uses the new NFS implementation by default.
II. Problem Description
When processing READDIR requests, the NFS server does not check that
it is in fact operating on a directory node. An attacker can use a
specially modified NFS client to submit a READDIR request on a file,
causing the underlying filesystem to interpret that file as a
directory.
III. Impact
The exact consequences of an attack depend on the amount of input
validation in the underlying filesystem:
- If the file resides on a UFS filesystem on a little-endian server,
an attacker can cause random heap corruption with completely
unpredictable consequences.
- If the file resides on a ZFS filesystem, an attacker can write
arbitrary data on the stack. It is believed, but has not been
confirmed, that this can be exploited to run arbitrary code in
kernel context.
Other filesystems may also be vulnerable.
IV. Workaround
Systems that do not provide NFS service are not vulnerable. Neither
are systems that do but use the old NFS implementation, which is the
default in FreeBSD 8.x.
To determine which implementation an NFS server is running, run the
following command:
# kldstat -v | grep -cw nfsd
This will print 1 if the system is running the new NFS implementation,
and 0 otherwise.
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.
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 http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch
# fetch http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch.asc
# gpg --verify nfsserver.patch.asc
b) Apply the patch.
# cd /usr/src
# patch < /path/to/patch
c) Recompile your kernel as described in
<URL:http://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the
system.
3) 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
VI. Correction details
The following list contains the revision numbers of each file that was
corrected in FreeBSD.
Branch/path Revision
- -------------------------------------------------------------------------
stable/8/ r250058
releng/8.3/ r250059
releng/8.4/ r250062
stable/9/ r250060
releng/9.1/ r250061
- -------------------------------------------------------------------------
VII. References
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3266
The latest revision of this advisory is available at
http://security.FreeBSD.org/advisories/FreeBSD-SA-13:05.nfsserver.asc
-----BEGIN PGP SIGNATURE-----
iEYEARECAAYFAlF+18oACgkQFdaIBMps37J1PACgm+zcbGd6xF1hkpvFVJbbwR0Q
9PoAnivbP1R0qXFyTlF/t3+sUYcxBtfQ
=polM
-----END PGP SIGNATURE-----
Michael Schnell
2013-Apr-29 21:13 UTC
[FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-13:05.nfsserver
Hi, thanks for the warning. But the link for the source patch is not working for me: http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch Greetings Michael On Mon, 29 Apr 2013, FreeBSD Security Advisories wrote:> -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > ============================================================================> FreeBSD-SA-13:05.nfsserver Security Advisory > The FreeBSD Project > > Topic: Insufficient input validation in the NFS server > > Category: core > Module: nfsserver > Announced: 2013-04-29 > Credits: Adam Nowacki > Affects: All supported versions of FreeBSD. > Corrected: 2013-04-29 20:15:43 UTC (stable/8, 8.4-PRERELEASE) > 2013-04-29 20:15:47 UTC (releng/8.3, 8.3-RELEASE-p8) > 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC1-p1) > 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC2-p1) > 2013-04-29 20:15:55 UTC (stable/9, 9.1-STABLE) > 2013-04-29 20:16:00 UTC (releng/9.1, 9.1-RELEASE-p3) > CVE Name: CVE-2013-3266 > > For general information regarding FreeBSD Security Advisories, > including descriptions of the fields above, security branches, and the > following sections, please visit <URL:http://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 on local disks. FreeBSD includes server and client > implementations of NFS. > > FreeBSD 8.0 and onward has two NFS implementations: the original CSRG > NFSv2 and NFSv3 implementation and a new implementation which also > supports NFSv4. > > FreeBSD 9.0 and onward uses the new NFS implementation by default. > > II. Problem Description > > When processing READDIR requests, the NFS server does not check that > it is in fact operating on a directory node. An attacker can use a > specially modified NFS client to submit a READDIR request on a file, > causing the underlying filesystem to interpret that file as a > directory. > > III. Impact > > The exact consequences of an attack depend on the amount of input > validation in the underlying filesystem: > > - If the file resides on a UFS filesystem on a little-endian server, > an attacker can cause random heap corruption with completely > unpredictable consequences. > > - If the file resides on a ZFS filesystem, an attacker can write > arbitrary data on the stack. It is believed, but has not been > confirmed, that this can be exploited to run arbitrary code in > kernel context. > > Other filesystems may also be vulnerable. > > IV. Workaround > > Systems that do not provide NFS service are not vulnerable. Neither > are systems that do but use the old NFS implementation, which is the > default in FreeBSD 8.x. > > To determine which implementation an NFS server is running, run the > following command: > > # kldstat -v | grep -cw nfsd > > This will print 1 if the system is running the new NFS implementation, > and 0 otherwise. > > 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. > > 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 http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch > # fetch http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch.asc > # gpg --verify nfsserver.patch.asc > > b) Apply the patch. > > # cd /usr/src > # patch < /path/to/patch > > c) Recompile your kernel as described in > <URL:http://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the > system. > > 3) 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 > > VI. Correction details > > The following list contains the revision numbers of each file that was > corrected in FreeBSD. > > Branch/path Revision > - ------------------------------------------------------------------------- > stable/8/ r250058 > releng/8.3/ r250059 > releng/8.4/ r250062 > stable/9/ r250060 > releng/9.1/ r250061 > - ------------------------------------------------------------------------- > > VII. References > > http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3266 > > The latest revision of this advisory is available at > http://security.FreeBSD.org/advisories/FreeBSD-SA-13:05.nfsserver.asc > -----BEGIN PGP SIGNATURE----- > > iEYEARECAAYFAlF+18oACgkQFdaIBMps37J1PACgm+zcbGd6xF1hkpvFVJbbwR0Q > 9PoAnivbP1R0qXFyTlF/t3+sUYcxBtfQ > =polM > -----END PGP SIGNATURE----- > _______________________________________________ > freebsd-announce at freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-announce > To unsubscribe, send any mail to "freebsd-announce-unsubscribe at freebsd.org" >
Michael Schnell
2013-Apr-29 21:20 UTC
[FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-13:05.nfsserver
Okay, found the correct link: http://www.freebsd.org/security/patches/SA-13:05/nfsserver.patch http://www.freebsd.org/security/patches/SA-13:05/nfsserver.patch.asc Just a wrong SA number in the url. ;-) Greetings Michael On Mon, 29 Apr 2013, FreeBSD Security Advisories wrote:> -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > ============================================================================> FreeBSD-SA-13:05.nfsserver Security Advisory > The FreeBSD Project > > Topic: Insufficient input validation in the NFS server > > Category: core > Module: nfsserver > Announced: 2013-04-29 > Credits: Adam Nowacki > Affects: All supported versions of FreeBSD. > Corrected: 2013-04-29 20:15:43 UTC (stable/8, 8.4-PRERELEASE) > 2013-04-29 20:15:47 UTC (releng/8.3, 8.3-RELEASE-p8) > 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC1-p1) > 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC2-p1) > 2013-04-29 20:15:55 UTC (stable/9, 9.1-STABLE) > 2013-04-29 20:16:00 UTC (releng/9.1, 9.1-RELEASE-p3) > CVE Name: CVE-2013-3266 > > For general information regarding FreeBSD Security Advisories, > including descriptions of the fields above, security branches, and the > following sections, please visit <URL:http://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 on local disks. FreeBSD includes server and client > implementations of NFS. > > FreeBSD 8.0 and onward has two NFS implementations: the original CSRG > NFSv2 and NFSv3 implementation and a new implementation which also > supports NFSv4. > > FreeBSD 9.0 and onward uses the new NFS implementation by default. > > II. Problem Description > > When processing READDIR requests, the NFS server does not check that > it is in fact operating on a directory node. An attacker can use a > specially modified NFS client to submit a READDIR request on a file, > causing the underlying filesystem to interpret that file as a > directory. > > III. Impact > > The exact consequences of an attack depend on the amount of input > validation in the underlying filesystem: > > - If the file resides on a UFS filesystem on a little-endian server, > an attacker can cause random heap corruption with completely > unpredictable consequences. > > - If the file resides on a ZFS filesystem, an attacker can write > arbitrary data on the stack. It is believed, but has not been > confirmed, that this can be exploited to run arbitrary code in > kernel context. > > Other filesystems may also be vulnerable. > > IV. Workaround > > Systems that do not provide NFS service are not vulnerable. Neither > are systems that do but use the old NFS implementation, which is the > default in FreeBSD 8.x. > > To determine which implementation an NFS server is running, run the > following command: > > # kldstat -v | grep -cw nfsd > > This will print 1 if the system is running the new NFS implementation, > and 0 otherwise. > > 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. > > 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 http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch > # fetch http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch.asc > # gpg --verify nfsserver.patch.asc > > b) Apply the patch. > > # cd /usr/src > # patch < /path/to/patch > > c) Recompile your kernel as described in > <URL:http://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the > system. > > 3) 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 > > VI. Correction details > > The following list contains the revision numbers of each file that was > corrected in FreeBSD. > > Branch/path Revision > - ------------------------------------------------------------------------- > stable/8/ r250058 > releng/8.3/ r250059 > releng/8.4/ r250062 > stable/9/ r250060 > releng/9.1/ r250061 > - ------------------------------------------------------------------------- > > VII. References > > http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3266 > > The latest revision of this advisory is available at > http://security.FreeBSD.org/advisories/FreeBSD-SA-13:05.nfsserver.asc > -----BEGIN PGP SIGNATURE----- > > iEYEARECAAYFAlF+18oACgkQFdaIBMps37J1PACgm+zcbGd6xF1hkpvFVJbbwR0Q > 9PoAnivbP1R0qXFyTlF/t3+sUYcxBtfQ > =polM > -----END PGP SIGNATURE----- > _______________________________________________ > freebsd-announce at freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-announce > To unsubscribe, send any mail to "freebsd-announce-unsubscribe at freebsd.org" >
Please be advised that, when using freebsd-update(8) to install the patch for this security problem, freebsd-update will move the current kernel to /boot/kernel.old, and install a new GENERIC kernel in /boot/kernel, even if you have built a custom kernel and created a copy of the GENERIC kernel in /boot/GENERIC. The kernel in /boot/GENERIC is NOT updated, nor are the modules in that directory updated. What's more, if you did not build modules for your custom kernel, you will not get copies of the updated NFS modules. This is probably not the behavior most users who have built custom kernels will want or expect. (I would have hoped that the GENERIC kernel, its modules, and the kernel sources would be updated and that I'd be reminded to rebuild my custom kernel if necessary.) --Brett Glass At 02:55 PM 4/29/2013, FreeBSD Security Advisories wrote:>-----BEGIN PGP SIGNED MESSAGE----- >Hash: SHA1 > >============================================================================>FreeBSD-SA-13:05.nfsserver Security Advisory > The FreeBSD Project > >Topic: Insufficient input validation in the NFS server
Per olof Ljungmark
2013-May-01 10:06 UTC
[FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-13:05.nfsserver
Path to patch seems wrong? On 2013-04-29 22:55, FreeBSD Security Advisories wrote:> ============================================================================> FreeBSD-SA-13:05.nfsserver Security Advisory > The FreeBSD Project > > Topic: Insufficient input validation in the NFS server > > Category: core > Module: nfsserver > Announced: 2013-04-29 > Credits: Adam Nowacki > Affects: All supported versions of FreeBSD. > Corrected: 2013-04-29 20:15:43 UTC (stable/8, 8.4-PRERELEASE) > 2013-04-29 20:15:47 UTC (releng/8.3, 8.3-RELEASE-p8) > 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC1-p1) > 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC2-p1) > 2013-04-29 20:15:55 UTC (stable/9, 9.1-STABLE) > 2013-04-29 20:16:00 UTC (releng/9.1, 9.1-RELEASE-p3) > CVE Name: CVE-2013-3266 > > For general information regarding FreeBSD Security Advisories, > including descriptions of the fields above, security branches, and the > following sections, please visit <URL:http://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 on local disks. FreeBSD includes server and client > implementations of NFS. > > FreeBSD 8.0 and onward has two NFS implementations: the original CSRG > NFSv2 and NFSv3 implementation and a new implementation which also > supports NFSv4. > > FreeBSD 9.0 and onward uses the new NFS implementation by default. > > II. Problem Description > > When processing READDIR requests, the NFS server does not check that > it is in fact operating on a directory node. An attacker can use a > specially modified NFS client to submit a READDIR request on a file, > causing the underlying filesystem to interpret that file as a > directory. > > III. Impact > > The exact consequences of an attack depend on the amount of input > validation in the underlying filesystem: > > - If the file resides on a UFS filesystem on a little-endian server, > an attacker can cause random heap corruption with completely > unpredictable consequences. > > - If the file resides on a ZFS filesystem, an attacker can write > arbitrary data on the stack. It is believed, but has not been > confirmed, that this can be exploited to run arbitrary code in > kernel context. > > Other filesystems may also be vulnerable. > > IV. Workaround > > Systems that do not provide NFS service are not vulnerable. Neither > are systems that do but use the old NFS implementation, which is the > default in FreeBSD 8.x. > > To determine which implementation an NFS server is running, run the > following command: > > # kldstat -v | grep -cw nfsd > > This will print 1 if the system is running the new NFS implementation, > and 0 otherwise. > > 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. > > 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 http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch > # fetch http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch.asc > # gpg --verify nfsserver.patch.asc > > b) Apply the patch. > > # cd /usr/src > # patch < /path/to/patch > > c) Recompile your kernel as described in > <URL:http://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the > system. > > 3) 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 > > VI. Correction details > > The following list contains the revision numbers of each file that was > corrected in FreeBSD. > > Branch/path Revision > ------------------------------------------------------------------------- > stable/8/ r250058 > releng/8.3/ r250059 > releng/8.4/ r250062 > stable/9/ r250060 > releng/9.1/ r250061 > ------------------------------------------------------------------------- > > VII. References > > http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3266 > > The latest revision of this advisory is available at > http://security.FreeBSD.org/advisories/FreeBSD-SA-13:05.nfsserver.asc > _______________________________________________ > freebsd-announce at freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-announce > To unsubscribe, send any mail to "freebsd-announce-unsubscribe at freebsd.org" >-- Intersonic AB Registered in Solna, Sweden SE556539368201
Johann Kois
2013-May-01 15:23 UTC
[FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-13:05.nfsserver
You are using an old version of the Security Advisory. The path mentioned was fixed and the Security Advisory was re-released, also via email: http://docs.freebsd.org/cgi/getmsg.cgi?fetch=30985+0+current/freebsd-security Or use the link on the FreeBSD homepage to get directly to fixed version. jkois -- Johann Kois jkois(at)FreeBSD.org FreeBSD Documentation Project FreeBSD German Documentation Project - https://doc.bsdgroup.de On 05/01/2013 12:06, Per olof Ljungmark wrote:> Path to patch seems wrong? > > On 2013-04-29 22:55, FreeBSD Security Advisories wrote: >> ============================================================================>> FreeBSD-SA-13:05.nfsserver Security Advisory >> The FreeBSD Project >> >> Topic: Insufficient input validation in the NFS server >> >> Category: core >> Module: nfsserver >> Announced: 2013-04-29 >> Credits: Adam Nowacki >> Affects: All supported versions of FreeBSD. >> Corrected: 2013-04-29 20:15:43 UTC (stable/8, 8.4-PRERELEASE) >> 2013-04-29 20:15:47 UTC (releng/8.3, 8.3-RELEASE-p8) >> 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC1-p1) >> 2013-04-29 20:16:25 UTC (releng/8.4, 8.4-RC2-p1) >> 2013-04-29 20:15:55 UTC (stable/9, 9.1-STABLE) >> 2013-04-29 20:16:00 UTC (releng/9.1, 9.1-RELEASE-p3) >> CVE Name: CVE-2013-3266 >> >> For general information regarding FreeBSD Security Advisories, >> including descriptions of the fields above, security branches, and the >> following sections, please visit <URL:http://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 on local disks. FreeBSD includes server and client >> implementations of NFS. >> >> FreeBSD 8.0 and onward has two NFS implementations: the original CSRG >> NFSv2 and NFSv3 implementation and a new implementation which also >> supports NFSv4. >> >> FreeBSD 9.0 and onward uses the new NFS implementation by default. >> >> II. Problem Description >> >> When processing READDIR requests, the NFS server does not check that >> it is in fact operating on a directory node. An attacker can use a >> specially modified NFS client to submit a READDIR request on a file, >> causing the underlying filesystem to interpret that file as a >> directory. >> >> III. Impact >> >> The exact consequences of an attack depend on the amount of input >> validation in the underlying filesystem: >> >> - If the file resides on a UFS filesystem on a little-endian server, >> an attacker can cause random heap corruption with completely >> unpredictable consequences. >> >> - If the file resides on a ZFS filesystem, an attacker can write >> arbitrary data on the stack. It is believed, but has not been >> confirmed, that this can be exploited to run arbitrary code in >> kernel context. >> >> Other filesystems may also be vulnerable. >> >> IV. Workaround >> >> Systems that do not provide NFS service are not vulnerable. Neither >> are systems that do but use the old NFS implementation, which is the >> default in FreeBSD 8.x. >> >> To determine which implementation an NFS server is running, run the >> following command: >> >> # kldstat -v | grep -cw nfsd >> >> This will print 1 if the system is running the new NFS implementation, >> and 0 otherwise. >> >> 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. >> >> 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 http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch >> # fetch http://security.FreeBSD.org/patches/SA-03:15/nfsserver.patch.asc >> # gpg --verify nfsserver.patch.asc >> >> b) Apply the patch. >> >> # cd /usr/src >> # patch < /path/to/patch >> >> c) Recompile your kernel as described in >> <URL:http://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the >> system. >> >> 3) 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 >> >> VI. Correction details >> >> The following list contains the revision numbers of each file that was >> corrected in FreeBSD. >> >> Branch/path Revision >> ------------------------------------------------------------------------- >> stable/8/ r250058 >> releng/8.3/ r250059 >> releng/8.4/ r250062 >> stable/9/ r250060 >> releng/9.1/ r250061 >> ------------------------------------------------------------------------- >> >> VII. References >> >> http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3266 >> >> The latest revision of this advisory is available at >> http://security.FreeBSD.org/advisories/FreeBSD-SA-13:05.nfsserver.asc >> _______________________________________________ >> freebsd-announce at freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-announce >> To unsubscribe, send any mail to "freebsd-announce-unsubscribe at freebsd.org" >> >