CVE-2026-88049
Publication date 10 September 2026
Last updated 6 October 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| tesseract | 26.04 LTS resolute |
Fixed 5.5.0-1ubuntu0.1~esm1
|
| 24.04 LTS noble |
Fixed 5.3.4-1ubuntu0.1~esm1
|
|
| 22.04 LTS jammy |
Fixed 4.1.1-2.1ubuntu0.1~esm1
|
|
| 20.04 LTS focal |
Fixed 4.1.1-2ubuntu0.1~esm1
|
|
| 18.04 LTS bionic |
Fixed 4.00~git2288-10f4998a-2ubuntu0.1~esm1
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
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CVSS version:
Base score
8.6 · High
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
Base score
5.5 · Medium
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8882-1
- Tesseract vulnerabilities
- 6 October 2026