Integer overflow in the padding implementation in the opus_packet_parse_impl function in src/opus_decoder.c in Opus before 1.0.2, as used in Google Chrome before 25.0.1364.97 on Windows and Linux and before 25.0.1364.99 on Mac OS X and other products, allows remote attackers to cause a denial of service (out-of-bounds read) via a long packet.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.