Tesseract is an open source OCR engine. Prior to 5.5.3, a crafted .traineddata model loaded through TessBaseAPI::Init can cause SquishedDawg::readsquisheddawg in src/dict/dawg.cpp to accept an unterminated forward-edge run, after which SquishedDawg::Load calls numforwardedges(0) and lastedge in src/dict/dawg.h reads beyond edges, causing a heap out-of-bounds read and process crash before image processing. This issue is fixed in version 5.5.3.