Updated zlib packages that fix a buffer overflow vulnerability are now available.
Zlib is a general-purpose, patent-free, lossless data compression library that is used by many different programs. The function gzprintf within zlib, when called with a string longer than Z_PRINTF_BUFZISE (= 4096 bytes), can overflow without giving a warning. zlib-1.1.4 and earlier exhibit this behavior. There are no known exploits of the gzprintf overrun, and only a few programs, including rpm2html and gimp-print, are known to use the gzprintf function. The problem has been fixed by checking the length of the output string within gzprintf.