heimdal, a suite of software implementing the Kerberos protocol, has "a cross-realm vulnerability allowing someone with control over a realm to impersonate anyone in the cross-realm trust path."
For the current stable distribution (woody) this problem has been fixed in version 0.4e-7.woody.8.1.
For the unstable distribution (sid), this problem has been fixed in version 0.6.1-1.
We recommend that you update your heimdal package.
Upgrade Instructions --------------------
wget url will fetch the file for you dpkg -i file.deb will install the referenced file.
If you are using the apt-get package manager, use the line for sources.list as given below:
apt-get update will update the internal database apt-get upgrade will install corrected packages
You may use an automated update by adding the resources from the footer to the proper configuration.
Debian GNU/Linux 3.0 alias woody --------------------------------