Ubuntu Security Notice 587-1 – It was discovered that krb5 did not correctly handle certain krb4 requests. An unauthenticated remote attacker could exploit this flaw by sending a specially crafted traffic, which could expose sensitive information, cause a crash, or execute arbitrary code. A flaw was discovered in the kadmind service’s handling of file descriptors. An unauthenticated remote attacker could send specially crafted requests that would cause a crash, resulting in a denial of service. Only systems with configurations allowing large numbers of open file descriptors were vulnerable.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/64708/USN-587-1.txt
Source: https://packetstormsecurity.com/files/64708/Ubuntu-Security-Notice-587-1.html