Red Hat: utempter Symlink vulnerability
Summary
Summary
Utempter is a utility that allows terminal applications such as xterm andscreen to update utmp and wtmp without requiring root privileges.Steve Grubb discovered a flaw in Utempter which allowed device namescontaining directory traversal sequences such as '/../'. In combinationwith an application that trusts the utmp or wtmp files, this could allow alocal attacker the ability to overwrite privileged files using a symlink.Users should upgrade to this new version of utempter, which fixes thisvulnerability.
Solution
Before applying this update, make sure all previously released errata
relevant to your system have been applied.
To update all RPMs for your particular architecture, run:
rpm -Fvh [filenames]
where [filenames] is a list of the RPMs you wish to upgrade. Only those
RPMs which are currently installed will be updated. Those RPMs which are
not installed but included in the list will not be updated. Note that you
can also use wildcards (*.rpm) if your current directory *only* contains the
desired RPMs.
Please note that this update is also available via Red Hat Network. Many
people find this an easier way to apply updates. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:
up2date
This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.
If up2date fails to connect to Red Hat Network due to SSL
Certificate Errors, you need to install a version of the
up2date client with an updated certificate. The latest version of
up2date is available from the Red Hat FTP site and may also be
downloaded directly from the RHN website:
https://access.redhat.com
5. Bug IDs fixed ( for more info):
121332 - CAN-2004-0233 utempter directory traversal symlink attack
6. RPMs required:
Red Hat Enterprise Linux AS (Advanced Server) version 2.1:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.2.1EL.0.i386.rpm
ia64:
Available from Red Hat Network: utempter-0.5.5-1.2.1EL.0.ia64.rpm
Red Hat Linux Advanced Workstation 2.1:
SRPMS:
ia64:
Available from Red Hat Network: utempter-0.5.5-1.2.1EL.0.ia64.rpm
Red Hat Enterprise Linux ES version 2.1:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.2.1EL.0.i386.rpm
Red Hat Enterprise Linux WS version 2.1:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.2.1EL.0.i386.rpm
Red Hat Enterprise Linux AS version 3:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.i386.rpm
ia64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.ia64.rpm
ppc:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.ppc.rpm
s390:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.s390.rpm
s390x:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.s390x.rpm
x86_64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.x86_64.rpm
Red Hat Desktop version 3:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.i386.rpm
x86_64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.x86_64.rpm
Red Hat Enterprise Linux ES version 3:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.i386.rpm
ia64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.ia64.rpm
x86_64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.x86_64.rpm
Red Hat Enterprise Linux WS version 3:
SRPMS:
i386:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.i386.rpm
ia64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.ia64.rpm
x86_64:
Available from Red Hat Network: utempter-0.5.5-1.3EL.0.x86_64.rpm
7. Verification:
MD5 sum Package Name
417fb9a00960adc60d2480e76a1432e9 utempter-0.5.5-1.2.1EL.0.i386.rpm
36023598fdb8c619e3a7ddf3071eeda8 utempter-0.5.5-1.2.1EL.0.ia64.rpm
bfcd383f81642909da3b591dc501ea26 utempter-0.5.5-1.2.1EL.0.src.rpm
437cbd0cf70f4c106d8769022818046e utempter-0.5.5-1.3EL.0.i386.rpm
78a2997b4bfa09e8797aa8168db5ee99 utempter-0.5.5-1.3EL.0.ia64.rpm
fa912c642528d6d1785245c0bed610a3 utempter-0.5.5-1.3EL.0.ppc.rpm
d6bd211838e75ae01eed0ad10f638fae utempter-0.5.5-1.3EL.0.s390.rpm
95518a64083b9610d6d13d01991296cf utempter-0.5.5-1.3EL.0.s390x.rpm
bb78ec4f0201e337eca2a0da85d5aa3d utempter-0.5.5-1.3EL.0.src.rpm
39e382c6a8e6a1ec5e05c5ba9bad4ee8 utempter-0.5.5-1.3EL.0.x86_64.rpm
These packages are GPG signed by Red Hat for security. Our key is
available from
You can verify each package with the following command:
rpm --checksig -v
If you only wish to verify that each package has not been corrupted or
tampered with, examine only the md5sum with the following command:
md5sum
References
Package List
Topic
Topic
An updated utempter package that fixes a potential symlink vulnerability is
now available.
Relevant Releases Architectures
Red Hat Enterprise Linux AS (Advanced Server) version 2.1 - i386, ia64
Red Hat Linux Advanced Workstation 2.1 - ia64
Red Hat Enterprise Linux ES version 2.1 - i386
Red Hat Enterprise Linux WS version 2.1 - i386
Red Hat Enterprise Linux AS version 3 - i386, ia64, ppc, s390, s390x, x86_64
Red Hat Desktop version 3 - i386, x86_64
Red Hat Enterprise Linux ES version 3 - i386, ia64, x86_64
Red Hat Enterprise Linux WS version 3 - i386, ia64, x86_64
Bugs Fixed