CVE-2026-88053: CWE-787: Out-of-bounds Write in tesseract-ocr tesseract
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, Classify::ReadIntTemplates in src/classify/intproto.cpp reads NumClassPruners, NumClasses, and NumProtoSets from the TESSDATA_INTTEMP component of a crafted .traineddata file and uses those values as loop bounds without validating them against MAX_NUM_CLASS_PRUNERS, MAX_NUM_CLASSES, and MAX_NUM_PROTO_SETS. The loops store heap pointers into fixed-capacity ClassPruners and ProtoSets arrays in INT_TEMPLATES_STRUCT and INT_CLASS_STRUCT, so an oversized count causes heap out-of-bounds pointer writes during legacy-classifier initialization before OCR begins, resulting in heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.
AI Analysis
Technical Summary
Tesseract-ocr versions 5.5.3 and earlier contain a heap out-of-bounds write vulnerability in the Classify::ReadIntTemplates function within src/classify/intproto.cpp. The function reads NumClassPruners, NumClasses, and NumProtoSets from the TESSDATA_INTTEMP component of a crafted .traineddata file and uses these values as loop bounds without validating them against predefined maximum constants (MAX_NUM_CLASS_PRUNERS, MAX_NUM_CLASSES, MAX_NUM_PROTO_SETS). This lack of validation allows loops to write heap pointers beyond the fixed-capacity ClassPruners and ProtoSets arrays in INT_TEMPLATES_STRUCT and INT_CLASS_STRUCT, causing heap corruption before OCR processing begins. The vulnerability can lead to application crashes or potentially controlled memory corruption. No patch or fixed release is currently available.
Potential Impact
Exploitation of this vulnerability can result in heap corruption, which may cause application crashes or potentially allow an attacker to control memory corruption. This could impact the stability and security of applications using vulnerable versions of tesseract-ocr. There are no known exploits in the wild as of the latest information.
Mitigation Recommendations
No official fix or patch is available at this time. Users should monitor the vendor's advisory channels for updates. Until a patch is released, avoid processing untrusted or malicious .traineddata files to reduce risk.
CVE-2026-88053: CWE-787: Out-of-bounds Write in tesseract-ocr tesseract
Description
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, Classify::ReadIntTemplates in src/classify/intproto.cpp reads NumClassPruners, NumClasses, and NumProtoSets from the TESSDATA_INTTEMP component of a crafted .traineddata file and uses those values as loop bounds without validating them against MAX_NUM_CLASS_PRUNERS, MAX_NUM_CLASSES, and MAX_NUM_PROTO_SETS. The loops store heap pointers into fixed-capacity ClassPruners and ProtoSets arrays in INT_TEMPLATES_STRUCT and INT_CLASS_STRUCT, so an oversized count causes heap out-of-bounds pointer writes during legacy-classifier initialization before OCR begins, resulting in heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.
CVSS v4.0
Score 8.6high
Affected software
tesseract-ocr
tesseract
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 5.5.3 and earlier contain a heap out-of-bounds write vulnerability in the Classify::ReadIntTemplates function within src/classify/intproto.cpp. The function reads NumClassPruners, NumClasses, and NumProtoSets from the TESSDATA_INTTEMP component of a crafted .traineddata file and uses these values as loop bounds without validating them against predefined maximum constants (MAX_NUM_CLASS_PRUNERS, MAX_NUM_CLASSES, MAX_NUM_PROTO_SETS). This lack of validation allows loops to write heap pointers beyond the fixed-capacity ClassPruners and ProtoSets arrays in INT_TEMPLATES_STRUCT and INT_CLASS_STRUCT, causing heap corruption before OCR processing begins. The vulnerability can lead to application crashes or potentially controlled memory corruption. No patch or fixed release is currently available.
Potential Impact
Exploitation of this vulnerability can result in heap corruption, which may cause application crashes or potentially allow an attacker to control memory corruption. This could impact the stability and security of applications using vulnerable versions of tesseract-ocr. There are no known exploits in the wild as of the latest information.
Mitigation Recommendations
No official fix or patch is available at this time. Users should monitor the vendor's advisory channels for updates. Until a patch is released, avoid processing untrusted or malicious .traineddata files to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-09-09T21:22:45.434Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aa2ee7d555a9c516207cb27
Added to database: 09/10/2026, 17:53:01 UTC
Last enriched: 09/10/2026, 18:06:18 UTC
Last updated: 09/10/2026, 18:44:06 UTC
Views: 7
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