Ubuntu: DSA 229-2 Important: libz Buffer Overflow and Input Validation

Ilia Alshanetsky discovered several buffer overflows in libmcrypt, a
decryption and encryption library, that originates in from improper or
lacking input validation. By passing input which is longer then
expected to a number of functions (multiple functions are affected)
the user can successful make libmcrypt crash and may be able to insert
arbitrary, malicious, code which will be executed under the user
libmcrypt runs as, e.g. inside a web server.

Another vulnerability exists in the way libmcrypt loads algorithms via
libtool. When different algorithms are loaded dynamically, each time
an algorithm is loaded a small part of memory is leaked. In a
persistant enviroment (web server) this could lead to a memory
exhaustion attack that will exhaust all avaliable memory by launching
repeated requests at an application utilizing the mcrypt library.

For the current stable distribution (woody) this problem has been
fixed in version 2.5.0-1woody1.

The old stable distribution (potato) does not contain lib...