CVE-2026-88049
Tesseract: Heap out-of-bounds write in LSTM::Forward via na_/gate-matrix dimension mismatch
Description
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, prior .traineddata hardening added bounds checks to NetworkIO::CopyTimeStepGeneral and NetworkIO::Randomize in src/lstm/networkio.cpp but left NetworkIO::WriteTimeStepPart and NetworkIO::AddTimeStepPart unchecked. In LSTM::Forward in src/lstm/lstm.cpp, source_ is sized from the independently deserialized na_ field while the WriteTimeStepPart count is ns_, which comes from the CI gate WeightMatrix dim1() value. A crafted NT_LSTM layer can make ns_ much larger than na_, causing a heap out-of-bounds write during the first recognition step on the default LSTM engine and resulting in heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.
INFO
Published Date :
Sept. 10, 2026, 5:17 p.m.
Last Modified :
Sept. 14, 2026, 8:01 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Apply available patches or updates for Tesseract.
- Review and update Tesseract source code related to LSTM layers.
- Implement stricter bounds checking in NetworkIO functions.
- Consider recompiling Tesseract with hardening flags.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-88049.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-88049 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-88049
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-88049 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-88049 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Sep. 14, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:tesseract-ocr:tesseract_ocr:*:*:*:*:*:*:*:* versions up to (including) 5.5.3 Added Reference Type GitHub, Inc.: https://github.com/tesseract-ocr/tesseract/commit/b494ac18925f9d9aff9ef5815475de9943ab19bf Types: Patch Added Reference Type GitHub, Inc.: https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-jgq8-pprg-vc68 Types: Vendor Advisory Added Reference Type CISA-ADP: https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-jgq8-pprg-vc68 Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 10, 2026
Action Type Old Value New Value Added Reference https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-jgq8-pprg-vc68 Added SSVC {'id': 'CVE-2026-88049', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-10T17:12:06.792549Z'} -
New CVE Received by [email protected]
Sep. 10, 2026
Action Type Old Value New Value Added Description Tesseract is an open source OCR engine. In version 5.5.3 and earlier, prior .traineddata hardening added bounds checks to NetworkIO::CopyTimeStepGeneral and NetworkIO::Randomize in src/lstm/networkio.cpp but left NetworkIO::WriteTimeStepPart and NetworkIO::AddTimeStepPart unchecked. In LSTM::Forward in src/lstm/lstm.cpp, source_ is sized from the independently deserialized na_ field while the WriteTimeStepPart count is ns_, which comes from the CI gate WeightMatrix dim1() value. A crafted NT_LSTM layer can make ns_ much larger than na_, causing a heap out-of-bounds write during the first recognition step on the default LSTM engine and resulting in heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-787 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/88xxx/CVE-2026-88049.json">CVE-2026-88049</a> Added Reference https://github.com/tesseract-ocr/tesseract/commit/b494ac18925f9d9aff9ef5815475de9943ab19bf Added Reference https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-jgq8-pprg-vc68