tomcat7 - security update

Multiple security vulnerabilities have been discovered in the Tomcat
servlet and JSP engine, which may result in possible timing attacks to
determine valid user names, bypass of the SecurityManager, disclosure of
system properties, unrestricted access to global resources, arbitrary
file overwrites, and potentially escalation of privileges.

For the stable distribution (jessie), these problems have been fixed in
version 7.0.56-3+deb8u5.

We recommend that you upgrade your tomcat7 packages.