7.5 - RHSA-2005:327

Problem Description:

Updated telnet packages that fix two buffer overflow vulnerabilities are now available.

This update has been rated as having important security impact by the Red Hat Security Response Team.

2. 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 Red Hat Enterprise Linux AS version 4 - i386, ia64, ppc, s390, s390x, x86_64 Red Hat Enterprise Linux Desktop version 4 - i386, x86_64 Red Hat Enterprise Linux ES version 4 - i386, ia64, x86_64 Red Hat Enterprise Linux WS version 4 - i386, ia64, x86_64

3. Problem description:

The telnet package provides a command line telnet client. The telnet-server package includes a telnet daemon, telnetd, that supports remote login to the host machine.

Two buffer overflow flaws were discovered in the way the telnet client handles messages from a server. An attacker may be able to execute arbitrary code on a victim's machine if the victim can be tricked into connecting to a malicious telnet server. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the names CAN-2005-0468 and CAN-2005-0469 to these issues.

Additionally, the following bugs have been fixed in these erratum packages for Red Hat Enterprise Linux 2.1 and Red Hat Enterprise Linux 3:

- - telnetd could loop on an error in the child side process

- - There was a race condition in telnetd on a wtmp lock on some occasions

- - The command line in the process table was sometimes too long and caused bad output from the ps command

- - The 8-bit binary option was not working

Users of telnet should upgrade to this updated package, which contains backported patches to correct these issues.

Red Hat would like to thank iDEFENSE for their responsible disclosure of this issue.

4. Solution:

Before applying this update, make sure that all previously-released errata relevant to your system have been applied. Use Red Hat Network to download and update your packages. To launch the Red Hat Update Agent, use the following command:

up2date

For information on how to install packages manually, refer to the following Web page for the System Administration or Customization guide specific to your system:

http://www.redhat.com/docs/manuals/enterprise/

5. Bug IDs fixed (http://bugzilla.redhat.com/):

126858 - Too long /proc/X/cmdline: bad ps output when piped to less/more 145004 - telnetd cleanup() race condition with syslog in signal handler 145636 - [PATCH] telnetd loops on child IO error 147003 - [RHEL3] telnetd cleanup() race condition with syslog in signal handler 151297 - CAN-2005-0469 slc_add_reply() Buffer Overflow Vulnerability 151301 - CAN-2005-0468 env_opt_add() Buffer Overflow Vulnerability