libwebp: heap-based buffer overflow in PutLE16()

A heap-based buffer overflow was found in libwebp in versions before 1.0.1 in PutLE16().

libwebp: out-of-bounds read in ApplyFilter()

A heap-based buffer overflow was found in libwebp in versions before 1.0.1 in ApplyFilter().

libwebp: out-of-bounds read in WebPMuxCreateInternal

A heap-based buffer overflow was found in libwebp in versions before 1.0.1 in GetLE16().

In libwebm through 2018-10-03, there is an abort caused by libwebm::Webm2Pes::InitWebmParser() that will lead to a DoS attack.

In libwebp 0.5.1, there is a double free bug in libwebpmux.