Vulnerability · Published Sep 10, 2026 · Assigned by GitHub_M

CVE-2026-88051Tesseract: Heap out-of-bounds write in GenericVector<T>::read due to independent reserved/size_used_ fields

High 8.6

In plain English

A high-severity out-of-bounds write in tesseract from tesseract-ocr. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)8.6High
Exploit odds (30 days)0.2%top 94.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Tesseract is an open source OCR engine. In version 5.5.3 and earlier, the callback form of GenericVector::read in src/ccutil/genericvector.h reads the independent int32 fields reserved and size_used_ from a .traineddata model without a cap or an invariant check. reserve(reserved) allocates the backing array, but the callback loop writes size_used_ elements. A crafted TESSDATA_INTTEMP component with version_id 4 or later can therefore set reserved to a small value and size_used_ to a large value when fontinfo_table_.read(fp, read_info) is called from src/classify/intproto.cpp, causing a heap out-of-bounds write of FontInfo structures, heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10tesseract5.3.4-11.el10_2ALSA-2026:95085
AlmaLinux:8tesseract4.1.1-7.el8_10ALSA-2026:95725
AlmaLinux:10tesseract-devel5.3.4-11.el10_2ALSA-2026:95085
AlmaLinux:8tesseract-devel4.1.1-7.el8_10ALSA-2026:95725
AlmaLinux:9tesseract-devel4.1.1-11.el9_8ALSA-2026:95086
Debian:12tesseractno fix listedDEBIAN-CVE-2026-88051
Debian:13tesseractno fix listedDEBIAN-CVE-2026-88051
Debian:14tesseractno fix listedDEBIAN-CVE-2026-88051
Rocky Linux:10tesseract0:5.3.4-11.el10_2RLSA-2026:95085
Rocky Linux:9tesseract0:4.1.1-11.el9_8RLSA-2026:95086
Ubuntu:26.10tesseractno fix listedUBUNTU-CVE-2026-88051

Affected products (as reported)

VendorProductVersions
tesseract-ocr tesseract <= 5.5.3

Weakness: CWE-787 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References