Vulnerability · Published Sep 10, 2026 · Assigned by GitHub_M
CVE-2026-88048Tesseract: Heap out-of-bounds write/read in FullyConnected::Forward via layer/weight-matrix dimension mismatch
High 8.6
In plain English
A high-severity out-of-bounds read 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.
Official description
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, FullyConnected::DeSerialize in src/lstm/fullyconnected.cpp does not validate the deserialized layer scalars ni_ and no_ against the weight-matrix dimensions. During FullyConnected::Forward, MatrixDotVector in src/lstm/weightmatrix.cpp writes w.dim1() results into temp_line, which is sized from no_, and reads w.dim2() minus one inputs from curr_input, which is sized from ni_. A crafted .traineddata NT_SOFTMAX layer can therefore use inconsistent dimensions to cause a heap out-of-bounds write and read on the default LSTM engine, resulting in heap corruption, a crash, information disclosure, or potentially controlled corruption. No fixed release is available as of this review.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | tesseract | 5.3.4-11.el10_2 | ALSA-2026:95085 |
| AlmaLinux:8 | tesseract | 4.1.1-7.el8_10 | ALSA-2026:95725 |
| AlmaLinux:10 | tesseract-devel | 5.3.4-11.el10_2 | ALSA-2026:95085 |
| AlmaLinux:8 | tesseract-devel | 4.1.1-7.el8_10 | ALSA-2026:95725 |
| AlmaLinux:9 | tesseract-devel | 4.1.1-11.el9_8 | ALSA-2026:95086 |
| Debian:12 | tesseract | no fix listed | DEBIAN-CVE-2026-88048 |
| Debian:13 | tesseract | no fix listed | DEBIAN-CVE-2026-88048 |
| Debian:14 | tesseract | no fix listed | DEBIAN-CVE-2026-88048 |
| Rocky Linux:10 | tesseract | 0:5.3.4-11.el10_2 | RLSA-2026:95085 |
| Rocky Linux:9 | tesseract | 0:4.1.1-11.el9_8 | RLSA-2026:95086 |
| Ubuntu:26.10 | tesseract | no fix listed | UBUNTU-CVE-2026-88048 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| tesseract-ocr | tesseract | <= 5.5.3 |
Weakness: CWE-125, 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