CVE-2026-73066: CWE-787: Out-of-bounds Write in tesseract-ocr tesseract
CVE-2026-73066 is a medium severity vulnerability in the open source OCR engine Tesseract. Versions prior to 5.5.3 are affected by an out-of-bounds write caused by an unchecked signed integer multiplication in the deserialization of a crafted .traineddata LSTM model component. This leads to an undersized output buffer but writes using the unwrapped element count during OCR recognition. The issue is fixed in version 5.5.3.
AI Analysis
Technical Summary
Tesseract OCR versions before 5.5.3 contain a heap out-of-bounds write vulnerability (CWE-787) triggered by loading a specially crafted .traineddata LSTM model. The vulnerability arises from an unchecked signed integer multiplication in the Convolve::DeSerialize function in src/lstm/convolve.cpp, which causes the convolution output-channel count to wrap. This results in an undersized forward-pass output buffer, while subsequent writes use the unwrapped count, causing heap corruption during OCR processing. This flaw is addressed in Tesseract version 5.5.3.
Potential Impact
An attacker can cause a heap out-of-bounds write during OCR recognition by supplying a malicious .traineddata LSTM model. This can lead to memory corruption, potentially causing application crashes or other undefined behavior. The CVSS 4.0 score is 6.8 (medium severity), indicating a significant but not critical impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade Tesseract to version 5.5.3 or later, where this vulnerability is fixed. No other mitigations are indicated or necessary according to the available data.
CVE-2026-73066: CWE-787: Out-of-bounds Write in tesseract-ocr tesseract
Description
CVE-2026-73066 is a medium severity vulnerability in the open source OCR engine Tesseract. Versions prior to 5.5.3 are affected by an out-of-bounds write caused by an unchecked signed integer multiplication in the deserialization of a crafted .traineddata LSTM model component. This leads to an undersized output buffer but writes using the unwrapped element count during OCR recognition. The issue is fixed in version 5.5.3.
CVSS v4.0
Score 6.8medium
Affected software
pkg:github/tesseract-ocr/tesseractRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Tesseract OCR versions before 5.5.3 contain a heap out-of-bounds write vulnerability (CWE-787) triggered by loading a specially crafted .traineddata LSTM model. The vulnerability arises from an unchecked signed integer multiplication in the Convolve::DeSerialize function in src/lstm/convolve.cpp, which causes the convolution output-channel count to wrap. This results in an undersized forward-pass output buffer, while subsequent writes use the unwrapped count, causing heap corruption during OCR processing. This flaw is addressed in Tesseract version 5.5.3.
Potential Impact
An attacker can cause a heap out-of-bounds write during OCR recognition by supplying a malicious .traineddata LSTM model. This can lead to memory corruption, potentially causing application crashes or other undefined behavior. The CVSS 4.0 score is 6.8 (medium severity), indicating a significant but not critical impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade Tesseract to version 5.5.3 or later, where this vulnerability is fixed. No other mitigations are indicated or necessary according to the available data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-10T19:37:41.443Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7b3853bf8831d539e79e51
Added to database: 08/11/2026, 14:57:23 UTC
Last enriched: 08/11/2026, 16:03:23 UTC
Last updated: 08/11/2026, 16:03:23 UTC
Views: 3
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