For the stable distribution (wheezy), these problems have been fixed in version 6:0.8.17-1.
For the unstable distribution (sid), these problems have been fixed in version 6:11.3-1.
We recommend that you upgrade your libav 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/