SuSe: nfs-utils denial of service vulnerability
Summary
______________________________________________________________________________
SuSE Security Announcement
Package: nfs-utils
Announcement-ID: SuSE-SA:2003:031
Date: Tue Jul 15 14:00:00 MEST 2003
Affected products: 7.2, 7.3, 8.0, 8.1, 8.2
SuSE Linux Database Server,
SuSE eMail Server III, 3.1
SuSE Linux Enterprise Server 7, 8
SuSE Linux Firewall on CD/Admin host
SuSE Linux Connectivity Server
SuSE Linux Office Server
SuSE Linux Desktop 1.0
Vulnerability Type: remote code execution
Severity (1-10): 7
SuSE default package: yes
Cross References: CAN-2003-0252
ISEC
Content of this advisory:
1) security vulnerability resolved: Off by one bug in rpc.mountd.
problem description, discussion, solution and upgrade information
2) pending vulnerabilities, solutions, workarounds:
- xpdf/acroread
- lbreakout
- Eterm
- gnats
- unzip
3) standard appendix (further information)
______________________________________________________________________________
1) problem description, brief discussion, solution, upgrade information
The nfs-utils package contains various programs to offer and manage
certain RPC services such as the rpc.mountd.
iSEC Security Research has reported an off-by-one bug in the xlog()
function used by the rpc.mountd. It is possible for remote attackers to use this off-by-one overflow to execute arbitrary code as root.
Some of the products listed above seem not vulnerable to this
one byte overflow due to the stack alignment generated by the compiler
during the build. Nevertheless, since there is no easy workaround except
shutting down the RPC services, an update is strongly recommended for
every product listed above.
This update needs to be applied to both NFS servers and clients,
as the vulnerable function is used by mountd and statd.
You can either restart these services manually, or use the
corresponding init scripts:
"rcnfsserver restart" (for the NFS server)
"rcnfs restart" (for the NFS client)
Depending on your setup, it may be less disruptive to restart
the two daemons manually.
Please download the update package for your distribution and verify its
integrity by the methods listed in section 3) of this announcement.
Then, install the package using the command "rpm -Fhv file.rpm" to apply
the update.
Our maintenance customers are being notified individually. The packages
are being offered to install from the maintenance web.
i386 Intel Platform:
SuSE-8.2:
964386359a4280b0f64b5d06cc0debb4
patch rpm(s):
5e67e844aa5d5c9d6fb3720f388813af
source rpm(s):
91695f1d03df64188c3a63126699a811
SuSE-8.1:
b212711af6445cb97773e30ed4284741
patch rpm(s):
8b267ea76f715f64b8a041c2f24cee07
source rpm(s):
6da708a468ca48dd4078cbeff2c842f6
SuSE-8.0:
3cec45e5a7fdac0e9d6c67d894e90b16
patch rpm(s):
5f86c33e9564e39df6f74c376d6d0ccd
source rpm(s):
f105acb95d3a770c4b142fd265bdf6a7
SuSE-7.3:
a4c43c562fc1d9ff65367795897d5fb5
source rpm(s):
dc56ab3deeb7a5ed6bde4e021ff35c10
SuSE-7.2:
1905a8a632eaf00dd5ad81f498ad6493
source rpm(s):
a048236b106c8a32bce936a39bdc0403
Sparc Platform:
SuSE-7.3:
176b1636fa49520b3f700d399af39203
source rpm(s):
2b3cd21df36acf2b6076993855ef179f
PPC Power PC Platform:
SuSE-7.3:
0af7e6f702231a3194063a2c99473bb4
source rpm(s):
6b4a8ea3c5e443d255e15123dc97b0e9
______________________________________________________________________________
2) Pending vulnerabilities in SuSE Distributions and Workarounds:
- xpdf/acroread
A problem regarding handling of external URLs by various
PDF readers has been reported by CERT. Attackers could execute
arbitrary commands as the user viewing the document by embedding
shell meta characters in URLs.
The xpdf PDF viewer as shipped with SuSE is not vulnerable to
this attack due to its configuration. For the acrobat PDF reader
we will provide updates on our ftp servers shortly.
- lbreakout
Various format string bugs in the code of the game lbreakout were
reported for version 2-2.5. These bugs can be exploited remotely.
SuSE Linux does not ship this vulnerable version of lbreakout.
- Eterm
A buffer overflow in eterm while handling the environment
variable ETERMPATH can lead to local privilege escalation.
SuSE do not ship eterm with higher privileges.
- gnats
Several security bugs were reported in gnats. These bugs will
be fixed and update packages will released soon.
- unzip
Unzip can be tricked into overwriting files by using special
zip archives. Fixed packages are available on our ftp servers.
______________________________________________________________________________
3) standard appendix: authenticity verification, additional information
- Package authenticity verification:
SuSE update packages are available on many mirror ftp servers all over
the world. While this service is being considered valuable and important
to the free and open source software community, many users wish to be
sure about the origin of the package and its content before installing
the package. There are two verification methods that can be used
independently from each other to prove the authenticity of a downloaded
file or rpm package:
1) md5sums as provided in the (cryptographically signed) announcement.
2) using the internal gpg signatures of the rpm package.
1) execute the command
md5sum
References