SUSE Security Announcement: Linux Kernel (SuSE-SA:2004:003)
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SUSE Security Announcement
Package: Linux Kernel (x86_64, AMD64)
Announcement-ID: SuSE-SA:2004:003
Date: Thursday, Jan 15th 2004 14:17 MET
Affected products: 9.0
SuSE Linux Enterprise Server 8,
Vulnerability Type: local system compromise
Severity (1-10): 6
SUSE default package: yes
Cross References:
Content of this advisory:
1) security vulnerability resolved:
- incorrect bounds checking in mremap()
- inproper CPU register access check in 32bit ptrace()
problem description, discussion, solution and upgrade information
2) pending vulnerabilities, solutions, workarounds:
- ethereal
- mc
- mod_gzip
- tripwire
- cvs
- gnome-filesystem
- XDM (XFree86, xf86)
- 3ddiag
- mod_auth_shadow
3) standard appendix (further information)
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1) problem description, brief discussion, solution, upgrade information
The do_mremap() function of the Linux Kernel is used to manage
(move, resize) Virtual Memory Areas (VMAs). By exploiting an incorrect
bounds check in do_mremap() during the remapping of memory it is
possible to create a VMA with the size of 0.
In normal operation do_mremap() leaves a memory hole of one page and
creates an additional VMA of two pages. In case of exploitation no
hole is created but the new VMA has a 0 bytes length.
The Linux Kernel's memory management is corrupted from this point
and can be abused by local users to gain root privileges.
Additionally Andi Kleen of SUSE LINUX found and fixed another bug
in the 32bit emulation of ptrace() which allows to modify CPU registers
from user-space to get full access to system ressources.
There is no temporary workaround for this bug.
Please reboot your system to run the new kernel.
AMD64 Platform:
SuSE-9.0:
ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/x86_64/k_deflt-2.4.21-178.x86_64.rpm
4896825f6399bebc80073dbbd74432cd
source rpm(s):
ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/src/k_deflt-2.4.21-178.src.rpm
e9afc5cbb5fc1dddb53e179a52d45f0a
ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/x86_64/k_smp-2.4.21-178.x86_64.rpm
8b7667ac6baf4aebd4961274cbdaa84e
source rpm(s):
ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/src/k_smp-2.4.21-178.src.rpm
ffc25e3c1b9a4ed4e5182ff5cbdd5c18
ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/x86_64/kernel-source-2.4.21-178.x86_64.rpm
9422ec31eb76d26a1dfaca8fb8542907
source rpm(s):
ftp://ftp.suse.com/pub/suse/x86_64/update/9.0/rpm/src/kernel-source-2.4.21-178.src.rpm
8acc26621600cc7411f964656c435389
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2) Pending vulnerabilities in SUSE Distributions and Workarounds:
- ethereal
Two remotely exploitable denial-of-service attacks were found in
the network analyzer ethereal.
New packages are available on our FTP servers.
- mc
By using a special combination of links in archive-files it is possible
to execute arbitrary commands while mc tries to open it in its VFS.
The packages will be released soon.
- mod_gzip (apache-contrib)
The apache module mod_gzip is vulnerable to remote code execution
while running in debug-mode. We do not ship this module in debug-mode
but future versions will include the fix.
Additionally the mod_gzip code was audited to fix more possible security
related bugs.
After more testing a new apache-contrib RPM package will be released.
- tripwire
Tripwire is a file integrity checker. The tripwire version on SuSE Linux
8.2 and 9.0 do crash when a requested file does not exists.
New packages will be available soon.
- cvs
The cvs server-side can be tricked to create files in the root filesystem
of the server by requesting malformed modules. The permissions on the
root filesystem normally prevent this malfunction. Additionally the
package will include a fix for a format-string bug.
New packages are available on our FTP servers.
- gnome-filesystem
A script included in the gnome-filesystem package handles temporary
files insecurely. This script is called by YaST2 with root
privileges. The bug can be exploited locally to create or overwrite
arbitrary files in the filesystem. The bug is fixed in our current
source-tree since November 2003.
New packages are available on our FTP servers.
- XDM (XFree86, xf86)
A missing check for failure conditions in the PAM code of XDM
can lead to local root access in conjunction with Kerberos
and alike. New packages will be released soon.
- 3ddiag
Some 3ddiag scripts handle temporary files in an insecure manner.
Thanks to Stefan Nordhausen <nordhaus at informatik.hu-berlin.de>
for reporting some of the issues.
New packages will be available on our FTP servers soon.
- mod_auth_shadow (apache-contrib)
This apache module ignores account expiration dates.
The update will be released together with mod_gzip.
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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
Hi! Is this the last kernel-patch? I think not. Within the last months there where more and more exploits on the web than ever. This is the right time to think over and do something in future security. This would be for example patching the SuSE-kernel with http://www.grsecurity.org/ or for minimum http://pax.grsecurity.net/ like some distributions already did. This does not help solving any new exploits but makes it a little bit harder to install not wanted software on servers because only allowed processes are allowed to work :-) This may be an optional part, but would improve more, than the "other" security-patch provided by SuSE. For me it worked. Philippe
Am Donnerstag, 15. Januar 2004 19:41 schrieb Philippe Vogel:
This would be for example patching the SuSE-kernel with http://www.grsecurity.org/ or for minimum http://pax.grsecurity.net/ like some distributions already did.
This does not help solving any new exploits but makes it a little bit harder to install not wanted software on servers because only allowed processes are allowed to work :-)
FULL ACK! Al
On Thu, 15 Jan 2004, Philippe Vogel wrote:
Hi!
Hi.
Is this the last kernel-patch? I think not. Within the last months there where more and more exploits on the web than ever. This is the right time to think over and do something in future security.
This would be for example patching the SuSE-kernel with http://www.grsecurity.org/ or for minimum http://pax.grsecurity.net/ like some distributions already did.
I started porting the PaX patch some days before XMAS but this job runs
with low priority at the moment.
Bye,
Thomas
--
Thomas Biege
Philippe Vogel wrote:
Within the last months there where more and more exploits on the web than ever. This is the right time to think over and do something in future security.
This would be for example patching the SuSE-kernel with http://www.grsecurity.org/ or for minimum http://pax.grsecurity.net/ like some distributions already did.
This does not help solving any new exploits but makes it a little bit harder to install not wanted software on servers because only allowed processes are allowed to work :-)
This may be an optional part, but would improve more, than the "other" security-patch provided by SuSE.
For me it worked.
Could you please expand on your "For me it worked" statement? Have you experienced any issues, even minor ones, with standard services like Samba, Apache, Postfix, etc..
Within the last months there where more and more exploits on the web
ever. This is the right time to think over and do something in future security.
This would be for example patching the SuSE-kernel with http://www.grsecurity.org/ or for minimum http://pax.grsecurity.net/
Philippe Vogel wrote: than like
some distributions already did.
This does not help solving any new exploits but makes it a little bit harder to install not wanted software on servers because only allowed processes are allowed to work :-)
This may be an optional part, but would improve more, than the "other" security-patch provided by SuSE.
For me it worked.
Could you please expand on your "For me it worked" statement? Have you experienced any issues, even minor ones, with standard services like Samba, Apache, Postfix, etc..
There are basic configurations for debian, but with knowledge on SuSE you will be able to configure it to your delight. There where no compliling problems (even without gcc 2.95 rc2 :-) ). You can make a cloneconfig with renaming the old Makefile and copying the Makefile from the SuSE - sources. After make cloneconfig you have to copy the original Makefile back again where it belonged. After that make dep bzImage modules modules_install install && /sbin/lilo (if you use lilo). Philippe
participants (5)
-
Al Bogner -
Avtar Gill -
Philippe Vogel -
Thomas Biege -
thomas＠suse.de