Use After Free
Use-after-free vulnerability in the matroska_read_seek function in libavformat/matroskadec.c in FFmpeg before 2.5.1, as used in Google Chrome before 40.0.2214.91, allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted Matroska file that triggers improper maintenance of tracks data.
CWE-416 - Use After Free
Use-after-free (UaF) vulnerability occurs when the application is using a pointer to memory that has been freed. Any attempt to read/write to a buffer after it is de-allocated allows memory corruption, sensitive information exposure, and can potentially lead to arbitrary code execution.