expat - security update

Multiple integer overflows have been discovered in Expat, an XML parsing
C library, which may result in denial of service or the execution of
arbitrary code if a malformed XML file is processed.

For the oldstable distribution (wheezy), this problem has been fixed
in version 2.1.0-1+deb7u2.

For the stable distribution (jessie), this problem has been fixed in
version 2.1.0-6+deb8u1.

For the unstable distribution (sid), this problem has been fixed in
version 2.1.0-7.

We recommend that you upgrade your expat packages.