USN-999-1: Kerberos vulnerability

5 October 2010

krb5 vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 10.10
  • Ubuntu 10.04 LTS


Remote authenticated users could crash the KDC.

Software Description

  • krb5 - MIT Kerberos


Mike Roszkowski discovered that the Kerberos KDC did not correctly validate the contents of certain messages. If an authenticated remote attacker sent specially crafted TGS requests, the KDC service would crash, leading to a denial of service.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 10.10
krb5-kdc - 1.8.1+dfsg-5ubuntu0.1
Ubuntu 10.04 LTS
krb5-kdc - 1.8.1+dfsg-2ubuntu0.3

To update your system, please follow these instructions:

In general, a standard system update will make all the necessary changes.