It was discovered that systems with microprocessors utilizing speculative execution and indirect branch prediction may allow unauthorized disclosure of information to an attacker with local user access via a side-channel analysis (Spectre v2). Multiple fixes were done already in linux kernel, intel-microcode etc. This fix adds amd-microcode-based IBPB support.

For Debian 8 Jessie, this problem has been fixed in version 3.20181128.1~deb8u1.

We recommend that you upgrade your amd64-microcode 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