Caldera Systems, Inc. Security Advisory
Subject: buffer overflow in inews
Advisory number: CSSA-2000-005.0
Issue date: 2000 March, 7
Cross reference: CSSA-1999-026.0
1. Problem Description
This advisory is a re-release of CSSA-1999-026.0, additionally
covering the OpenLinux eServer platform. Users of the OpenLinux 2.3
Desktop product do not need to take additional actions if you have
already upgraded to the inn package as update 016.
The ‘INN’ (InterNetNews) package contains the ‘inews’ binary,
which is used for injecting news articles into the server. ISC, the
maintainers of INN, have release a patch for several buffer
overflows in the passwd field handling and article header parsing
routines in inews, which allows any local user to gain group ‘news’
access.
Since other parts of INN use group writeable files with ‘news’
permissions and due to inherent complexity of INN a further chain
of exploits could be used to gain ‘news’ user access and
(theoretically) ‘root’ access.
2. Vulnerable Versions
System Package
-----------------------------------------------------------
OpenLinux Desktop 2.3 All packages previous to
inn-2.2.1-1
(see update 016)
OpenLinux eServer 2.3 All packages previous to
inn-2.2.2-2
3. Solution
Workaround:
chmod 550 /usr/libexec/inn/bin/inews
Since the ‘rnews’ binary might also be affected, if you do not
use UUCP you should do:
chown news /usr/libexec/inn/rnews chgrp news
/usr/libexec/inn/rnews chmod 500 /usr/libexec/inn/rnews
The proper solution is to upgrade to the fixed packages
rpm -U inn-2.2.1-1.i386.rpm
4. OpenLinux Desktop 2.3
Fixed packages released with update 016
5. OpenLinux eServer 2.3
5.1 Location of Fixed Packages
The upgrade packages can be found on Caldera’s FTP site at:
ftp://ftp.calderasystems.com/pub/eServer/updates/2.3/current/RPMS/
The corresponding source code package can be found at:
ftp://ftp.calderaystems.com/pub/eServer/updates/2.3/current/SRPMS
5.2 Verification
e7cbfb0fbe8e589b78bc75c621a9c2ba RPMS/inn-2.2.2-2.i386.rpm
d6f11e575bf268920d24faba9fdc62fe SRPMS/inn-2.2.2-2.src.rpm
5.3 Installing Fixed Packages
Upgrade the affected packages with the following commands:
rpm -F inn-2.2.2-2.i386.rpm
6. References
This and other Caldera security resources are located at:
http://www.calderasystems.com/support/security/index.html
7. Disclaimer
Caldera Systems, Inc. is not responsible for the misuse of any
of the information we provide on this website and/or through our
security advisories. Our advisories are a service to our customers
intended to promote secure installation and use of Caldera
OpenLinux.