local privilege escalation in libmcrypt

Libmcrypt is a data encryption library that is able to load crypto- modules at run-time by using libltdl. Versions of libmcrypt prior to 2.5.5 include several buffer overflows that can be triggered by passing very long input to the mcrypt_* functions. The way libmcrypt handles dynamic crypto-modules via libltdl leads to memory-leaks that can cause a Denial-of-Service condition. This Problem can just be solved by linking modules static. This security update does not solve the memory-leak problem to avoid compatibility problems. Future releases of libmcrypt will be linked statically.