Several issues have been discovered in the MySQL database server. The vulnerabilities are addressed by upgrading MySQL to the new upstream version 5.5.49. Please see the MySQL 5.5 Release Notes and Oracle's Critical Patch Update advisory for further details:
For the stable distribution (jessie), these problems have been fixed in version 5.5.49-0+deb8u1.
We recommend that you upgrade your mysql-5.5 packages.
Further information about Debian Security Advisories, how to apply these updates to your system and frequently asked questions can be found at: https://www.debian.org/security/