Hans Jerry Illikainen discovered that libgd2, a library for programmatic graphics creation and manipulation, suffers of a signedness vulnerability which may result in a heap overflow when processing specially crafted compressed gd2 data. A remote attacker can take advantage of this flaw to cause an application using the libgd2 library to crash, or potentially, to execute arbitrary code with the privileges of the user running the application.
For the oldstable distribution (wheezy), this problem has been fixed in version 2.0.36~rc1~dfsg-6.1+deb7u2.
For the stable distribution (jessie), this problem has been fixed in version 2.1.0-5+deb8u1.
For the unstable distribution (sid), this problem has been fixed in version 2.1.1-4.1.
We recommend that you upgrade your libgd2 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/
Thanks for your request. This issue you reported is a known issue. For more information, please visit our support forums.