Tesseract is an open source OCR engine. Prior to 5.5.4, WeightMatrix::DeSerialize trusts a mode byte from a traineddata LSTM network and calls WeightMatrix::DeSerializeOld when kDoubleFlag is clear. In default FAST_FLOAT builds, DeSerializeOld invokes ASSERT_HOST instead of returning an error, so loading a crafted model through TessBaseAPI::Init terminates the process and causes denial of service. This issue is fixed in version 5.5.4.