Tesseract: Heap out-of-bounds write in LSTM Convolve layer via crafted .traineddata (CVE-2026-73066) | HOL Guard CVE

Medium · CVSS 6.8CVE-2026-73066

Tesseract: Heap out-of-bounds write in LSTM Convolve layer via crafted .traineddata

Answer in brief

CVE-2026-73066 records a Medium severity (CVSS 6.8) vulnerability in Tesseract: Heap out-of-bounds write in LSTM Convolve layer via crafted .traineddata. The current sources do not mark it as known exploited. The current feed maps tesseract-ocr/tesseract (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 11, 2026Updated Sep 9, 2026Source checked Sep 25, 2026First seen by HOL Aug 11, 2026Material review Sep 9, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.8
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 6.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps tesseract-ocr/tesseract (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
tesseract-ocr/tesseractgeneric	< 5.5.3	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for tesseract-ocr/tesseract.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Aug 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 9, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 11, 2026

Sources and claim methodology

Upstream source description

Tesseract is an open source OCR engine. Prior to 5.5.3, a crafted .traineddata LSTM model component loaded through Tesseract's deserializer can cause an unchecked signed integer multiplication in Convolve::DeSerialize in src/lstm/convolve.cpp to wrap the convolution output-channel count, undersizing the forward-pass output buffer while writes use the unwrapped element count and causing a heap out-of-bounds write during OCR recognition. This issue is fixed in version 5.5.3.

Quoted source text, attributed separately from HOL analysis.