MIT Kerberos 5 is vulnerable to a Denial of Service attack and remote execution of arbitrary code, possibly leading to the compromise of the entire Kerberos realm.
Background ==========
MIT Kerberos 5 is the free implementation of the Kerberos network authentication protocol by the Massachusetts Institute of Technology.
Daniel Wachdorf discovered that MIT Kerberos 5 could corrupt the heap by freeing unallocated memory when receiving a special TCP request (CAN-2005-1174). He also discovered that the same request could lead to a single-byte heap overflow (CAN-2005-1175). Magnus Hagander discovered that krb5_recvauth() function of MIT Kerberos 5 might try to double-free memory (CAN-2005-1689).
Impact ======
Although exploitation is considered difficult, a remote attacker could exploit the single-byte heap overflow and the double-free vulnerability to execute arbitrary code, which could lead to the compromise of the whole Kerberos realm. A remote attacker could also use the heap corruption to cause a Denial of Service.
Workaround ==========
There are no known workarounds at this time.
Resolution ==========
All MIT Kerberos 5 users should upgrade to the latest available version:
Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at http://bugs.gentoo.org.
License =======
Copyright 2005 Gentoo Foundation, Inc; referenced text belongs to its owner(s).
The contents of this document are licensed under the Creative Commons - Attribution / Share Alike license.