Several vulnerabilities were discovered in libxml2, a library providing support to read, modify and write XML and HTML files. A remote attacker could provide a specially crafted XML or HTML file that, when processed by an application using libxml2, would cause a denial-of-service against the application, information leaks, or potentially, the execution of arbitrary code with the privileges of the user running the application.
For the oldstable distribution (jessie), these problems have been fixed in version 2.9.1+dfsg1-5+deb8u5.
For the stable distribution (stretch), these problems have been fixed in version 2.9.4+dfsg1-2.2+deb9u1.
For the unstable distribution (sid), these problems have been fixed in version 2.9.4+dfsg1-3.1.
We recommend that you upgrade your libxml2 packages.