# CVE-2026-102728: Out-of-bounds reads in NetX Secure client-side handshake parsing (ServerHello and HelloVerifyRequest)

Status: published. Published: 2026-09-29. Updated: 2026-11-04.

In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the NetX Secure TLS client's ServerHello parser and DTLS client's HelloVerifyRequest parser read fields before checking that the message is long enough to contain them. A malicious server or an on-path attacker can make the client read up to three bytes past a handshake message, which can fault the client on targets with memory protection.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Eclipse Foundation / Eclipse ThreadX NetX Duo: ≥ 6.0; ≤ 6.5.2.202603a (affected, custom); 6.5.2.202603b (unaffected, custom). Source: CNA: eclipse

## Severity and prioritization

- CVSS 4.0: 6.3 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N; source: CNA: eclipse

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N; source: ADP: CISA-ADP

- CVSS 4.0: 6.3 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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; source: NVD: emo@eclipse.org

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N; source: NVD: 134c704f-9b21-4f2e-91b3-4a467353bcc0

- CISA KEV: No listing in collected sources

- EPSS: 0.24% as of 2026-11-04; percentile 15.85%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-126

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-4q67-8385-j6m5 (CNA: eclipse)

- https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-4q67-8385-j6m5 (emo@eclipse.org)

## Provenance

- CNA: eclipse: https://www.cve.org/CVERecord?id=CVE-2026-102728; retrieved 2026-11-04; source updated 2026-11-04

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-102728; retrieved 2026-11-04; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-102728; retrieved 2026-11-05; source updated Not reported

Revision: dc05afb917a44d9a8da81d76ef4d0889c42edfe7954a8250a64c80897b7b5614

Canonical: https://y2.dev/cve/CVE-2026-102728

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