Medium 6.9Published Sep 10, 2026

CVE-2026-88050Tesseract: Out-of-bounds write in UnicharCompress via unvalidated recoder code values

Updated under an hour ago (2026-10-19 09:20 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for tesseract-ocr tesseract

Exploited in the last 30 days

Tesseract is an open source OCR engine. In version 5.5.3 and earlier, RecodedCharID::DeSerialize in src/ccutil/unicharcompress.h validates length_ but accepts negative code_ values from a crafted .traineddata recoder component. UnicharCompress::ComputeCodeRange in src/ccutil/unicharcompress.cpp can consequently produce code_range_ equal to zero, after which SetupDecoder indexes is_valid_start_ with the negative code on a size-zero vector. The resulting out-of-bounds bit write uses a large wrapped index and reliably causes a wild-address crash or allocation failure on the default LSTM engine. No fixed release is available as of this review.

CVSS: 6.9 MEDIUM (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Sep 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

tesseract-ocr tesseract tesseract_ocr:tesseract (from the name)	through 5.5.3	CNA record
tesseract-ocr tesseract_ocr tesseract-ocr:tesseract_ocr	through 5.5.3	NVD

References

https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-7v9h-3q3m-w68gx-refsource-confirm, vendor-advisory
https://github.com/tesseract-ocr/tesseract/commit/c94a5532ee04db5a4919542832fd94caee5ea58fx-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.