# CVE-2026-92843: Out-of-bounds Read via the TLS 1.3 Certificate extensions_length in NetX Secure


- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 20 Oct 2026
- **Updated:** 20 Oct 2026
- **Also known as:** GHSA-4m85-f9qh-q3jv

## What is CVE-2026-92843?

CVE-2026-92843 is a high-severity vulnerability in Eclipse ThreadX - NetX Duo, published on 20 Oct 2026. 

### Official description

A missing bounds check in the TLS 1.3 Certificate-message parser of NetX Secure lets a malicious TLS 1.3 server trigger an unsigned-integer underflow and a subsequent heap out-of-bounds read in any peer that processes a remote Certificate message. It is reachable pre-authentication, during the normal handshake, before certificate verification completes.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-92843?


## How do I fix CVE-2026-92843?

No fix has been published for CVE-2026-92843 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-92843 being exploited?

There is no known exploitation of CVE-2026-92843 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-92843 and fix it if it is affected.

What it is: CVE-2026-92843 is a high-severity vulnerability in Eclipse ThreadX - NetX Duo, published on 20 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-92843 in the wild and no public exploit code.

Affected product: Eclipse ThreadX - NetX Duo. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-92843/ (Markdown: https://insights.sbomify.com/CVE-2026-92843/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-92843
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-92843
- OSV: https://osv.dev/vulnerability/CVE-2026-92843

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-92843/
Summaries are generated and may contain mistakes; the official description above is the record.