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SuSE Security Announcement: scotty

Jul 02, 2001, 21:30 (0 Talkback[s])

SuSE Security Announcement

Package: scotty
Announcement-ID: SuSE-SA:2001:023
Date: Monday, Jul 2nd 2001 15:30 MEST
Affected SuSE versions: (6.0, 6.1, 6.2,) 6.3, 6.4, 7.0, 7.1, 7.2
Vulnerability Type: local privilege escalation
Severity (1-10): 5
SuSE default package: no
Other affected systems: yes

Content of this advisory:
1) security vulnerability resolved: scotty/ntping
problem description, discussion, solution and upgrade information
2) pending vulnerabilities, solutions, workarounds
3) standard appendix (further information)


1) problem description, brief discussion, solution, upgrade information

Tkined's Scotty is a Tcl extension to build network management
applications. Ntping, a ping/traceroute program, is part of the Scotty package.
It's failure is to read a hostname as commandline option without checking
the size. This leads to a bufferoverrun, that could be used to gain root privileges,
because ntping is installed setuid root and is executeable by everyone.

As a temporary workaround you could remove the setuid bit:
/bin/chmod u-s /usr/bin/ntping
or just allow trusted users the access the binary:
/bin/chown root.trusted /usr/bin/ntping
/bin/chmod 4750 /usr/bin/ntping
Also add these permission changes to /etc/permissions.local.

i386 Intel Platform:

source rpm:

source rpm:

source rpm:

Sparc Platform:

source rpm:

AXP Alpha Platform:

source rpm:

source rpm:

source rpm:

PPC PowerPC Platform:

source rpm:

source rpm:


2) Pending vulnerabilities in SuSE Distributions and Workarounds:

- dqs
dex@raza-mexicana.org has found an exploitable buffer overflow bug in
the dsh program from the dqs package on SuSE Linux distributions.
To workaround the problem, do "chmod -s /usr/bin/dsh" and change the
files /etc/permissions* to reflect the change. If you do not need the
dqs package, then deinstall it (rpm -e dqs).
Packages for most of the supported SuSE Linux distributions are
available at the usual location ftp://ftp.suse.com/pub/suse/<arch>/<dist>
for download and installation/update. Do not forget to change the files
/etc/permissions* to remove the suid-bit from the dsh program. Please
note that we will not issue a dedicated security announcement for this
specific bug.

- pcp
Paul Starzetz discovered a security weakness in the setuid root program
/usr/share/pcp/bin/pmpost. The common library in pcp trusts the
environment that has been supplied by the user, regardless of privileged
execution or not. By consequence, a user can specify the configuration
file and therefore write to files owned by root. The problem is not based
on insecurely following symlinks as stated by Paul Starzetz.
The pcp package is not installed by default in SuSE Linux distributions.
We have provided update packages for the SuSE Linux distributions version
7.1 and 7.2 that remove the setuid bit from the pmpost binary. Versions
before SuSE-7.1 were not affected because the setuid bit was not set.
We thank Keith Owens and Mark Goodwin from Silicon Graphics for responding
quickly and for publishing a new version of the pcp package which will
be included in future releases of the SuSE Linux distribution. For more
information see the /usr/share/doc/packages/pcp directory of your SuSE
Linux installation after installing the update package, or go to
obtained from http://oss.sgi.com/projects/pcp/download .
Please note that there will not be a dedicated security announcement
for this specific bug.

- fetchmail (fetchml)
New fetchmail packages are available on the ftp server. The packages
cure a buffer overflow that can be exploited by sending a victim a
specially designed email, waiting for the victim's fetchmail program
to pick up the email. We are preparing a security announcement for this

- openssh
update packages for the openssh package after (and including) SuSE-6.4
are available on our ftp servers ftp.suse.de (for < 7.1) or
ftp.suse.com (for >= 7.1). We are currently checking for a non-security
related irregularity in sshd's behaviour under faulty setup conditions.

- exim
SuSE Linux distributions do not contain the exim Mail Transport Agent
(See http://www.exim.org/ for details) and are therefore not susceptible
to the recently found security-related bugs.

- webmin
SuSE Linux distributions do not contain the webmin administration
web frontend (See http://www.webmin.org/ for details) and are therefore
not vulnerable to the recently found security-related problems in the


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 <name-of-the-file.rpm>
after you downloaded the file from a SuSE ftp server or its mirrors.
Then, compare the resulting md5sum with the one that is listed in the
announcement. Since the announcement containing the checksums is
cryptographically signed (usually using the key security@suse.de),
the checksums show proof of the authenticity of the package.
We disrecommend to subscribe to security lists which cause the
email message containing the announcement to be modified so that
the signature does not match after transport through the mailing
list software.
Downsides: You must be able to verify the authenticity of the
announcement in the first place. If RPM packages are being rebuilt
and a new version of a package is published on the ftp server, all
md5 sums for the files are useless.

2) rpm package signatures provide an easy way to verify the authenticity
of an rpm package. Use the command
rpm -v --checksig <file.rpm>
to verify the signature of the package, where <file.rpm> is the
filename of the rpm package that you have downloaded. Of course,
package authenticity verification can only target an uninstalled rpm
package file.
a) gpg is installed
b) The package is signed using a certain key. The public part of this
key must be installed by the gpg program in the directory
~/.gnupg/ under the user's home directory who performs the
signature verification (usually root). You can import the key
that is used by SuSE in rpm packages for SuSE Linux by saving
this announcement to a file ("announcement.txt") and
running the command (do "su -" to be root):
gpg --batch; gpg < announcement.txt | gpg --import
SuSE Linux distributions version 7.1 and thereafter install the
key "build@suse.de" upon installation or upgrade, provided that
the package gpg is installed. The file containing the public key
is placed at the toplevel directory of the first CD (pubring.gpg)
and at ftp://ftp.suse.com/pub/suse/pubring.gpg-build.suse.de .

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