Use-after-free vulnerability in the EbmlMaster::Read function in libEBML before 1.3.3 allows context-dependent attackers to have unspecified impact via a "deeply nested element with infinite size" followed by another element of an upper level in an EBML document.
https://github.com/Matroska-Org/libebml/commit/88409e2a94dd3b40ff81d08bf6d92f486d036b24
https://github.com/Matroska-Org/libebml/blob/release-1.3.3/ChangeLog
http://www.talosintelligence.com/reports/TALOS-2016-0037/
http://www.securityfocus.com/bid/94924
http://www.debian.org/security/2016/dsa-3538
http://lists.opensuse.org/opensuse-updates/2016-01/msg00035.html
http://lists.matroska.org/pipermail/matroska-users/2015-October/006985.html