CVE-2026-88049: high-severity vulnerability in tesseract-ocr tesseract
Tesseract: Heap out-of-bounds write in LSTM::Forward via na_/gate-matrix dimension mismatch
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.6epss 0.1%
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, prior .traineddata hardening added bounds checks to NetworkIO::CopyTimeStepGeneral and NetworkIO::Randomize in src/lstm/networkio.cpp but left NetworkIO::WriteTimeStepPart and NetworkIO::AddTimeStepPart unchecked. In LSTM::Forward in src/lstm/lstm.cpp, source_ is sized from the independently deserialized na_ field while the WriteTimeStepPart count is ns_, which comes from the CI gate WeightMatrix dim1() value. A crafted NT_LSTM layer can make ns_ much larger than na_, causing a heap out-of-bounds write during the first recognition step on the default LSTM engine and resulting in heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
tesseract-ocr · tesseractRelated CVEs — tesseract-ocr tesseract
In the same product, most dangerous first.
CVE-2026-119341NONETesseract: File-controlled pointers still reach `delete` in ADAPT_CLASS_STRUCT destructorEPSS 0.3%CVE-2026-88052HIGHTesseract: Heap out-of-bounds write in UNICHARSET::load_via_fgets via count/insert desynchronizationEPSS 0.2%CVE-2026-88053HIGHTesseract: Heap out-of-bounds write in Classify::ReadIntTemplates via unvalidated counts in crafted .traineddataEPSS 0.2%CVE-2026-88048HIGHTesseract: Heap out-of-bounds write/read in FullyConnected::Forward via layer/weight-matrix dimension mismatchEPSS 0.2%CVE-2026-88051HIGHTesseract: Heap out-of-bounds write in GenericVector<T>::read due to independent reserved/size_used_ fieldsEPSS 0.2%CVE-2026-119339MEDIUMTesseract: Crafted LSTM model (`WeightMatrix` mode byte) triggers `ASSERT_HOST` abort in `WeightMatrix::DeSerializeOld` under `FAST_FLOAT` — Denial of ServiceEPSS 0.2%