A remote Denial of Service vulnerability was discovered in the heimdal implementation of the telnet daemon. A remote attacker could force the server to crash due to a NULL de-reference before the user logged in, resulting in inetd turning telnetd off because it forked too fast.
Please note that the heimdal-servers package is not officially supported in Ubuntu (it is in the ‘universe’ component of the archive). However, this affects you if you use a customized version built from the heimdal source package (which is supported).
18 February 2006
A security issue affects these releases of Ubuntu and its derivatives:
A remote Denial of Service vulnerability was discovered in the heimdal implementation of the telnet daemon. A remote attacker could force the server to crash due to a NULL de-reference before the user logged in, resulting in inetd turning telnetd off because it forked too fast.
Please note that the heimdal-servers package is not officially supported in Ubuntu (it is in the ‘universe’ component of the archive). However, this affects you if you use a customized version built from the heimdal source package (which is supported).
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.