CVE-2026-88050 Tesseract: Out-of-bounds write in UnicharCompress via unvalidated recoder code values
An attacker can cause a crash or potentially execute code by providing a crafted traineddata file to the Tesseract OCR engine.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-88050?
CVE-2026-88050 is a medium-severity memory corruption vulnerability in tesseract-ocr tesseract, published on 10 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-787
Which versions are affected by CVE-2026-88050?
It affects 1 product.
Products include Tesseract-Ocr Tesseract Ocr.
How do I fix CVE-2026-88050?
No fix published yet.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-88050 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-88050 exists.
Other vulnerabilities in tesseract-ocr tesseract
- CVE-2026-88047 Tesseract: ReadNormProtos stack buffer overflow
- CVE-2026-88048 Tesseract: Heap out-of-bounds write/read in FullyConnected::Forward via layer/weight-matrix dimension mismatch
- CVE-2026-88049 Tesseract: Heap out-of-bounds write in LSTM::Forward via na_/gate-matrix dimension mismatch
- CVE-2026-88051 Tesseract: Heap out-of-bounds write in GenericVector<T>::read due to independent reserved/size_used_ fields
- CVE-2026-88053 Tesseract: Heap out-of-bounds write in Classify::ReadIntTemplates via unvalidated counts in crafted .traineddata
Sources
Also known as DEBIAN-CVE-2026-88050, ECHO-197a-e8b7-fcfe, GHSA-7v9h-3q3m-w68g, UBUNTU-CVE-2026-88050.