PYSEC-2026-2832 Integer Overflow or Wraparound in OpenCV

In opencv/modules/imgcodecs/src/grfmtpxm.cpp, function PxMDecoder::readData has an integer overflow when calculate srcpitch. If the image is from remote, may lead to remote code execution or denial of service. This affects OpenCV 3.3 corresponding to OpenCV-Python 3.3.0.9 and earlier...