Several issues have been found in zlib, a compression library. They are basically about improper big-endian CRC calculation, improper left shift of negative integers and improper pointer arithmetic.

For Debian 8 Jessie, these problems have been fixed in version 1:1.2.8.dfsg-2+deb8u1.

We recommend that you upgrade your zlib packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS