The opj_dwt_decode_1* functions in dwt.c in OpenJPEG, as used in PDFium in Google Chrome before 47.0.2526.73, allow remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via crafted JPEG 2000 data that is mishandled during a discrete wavelet transform.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.