CVE-2026-103416 Eclipse Foundation CVE debrief

Who should care

Defenders responsible for Eclipse ThreadX NetX Duo deployments, particularly those using version 6.5.1.202602 or earlier, should assess exposure and prioritize patching. Network administrators, security teams, and developers integrating this library should verify server certificate authentication and TLS 1.3 configuration, and monitor for suspicious activity.

Why it matters

CVE-2026-103416 is a critical vulnerability in Eclipse ThreadX NetX Duo 6.5.1.202602, allowing out-of-bounds write via TLS 1.3 handshake message cache. Defenders should assess exposure, prioritize patching, and verify configurations to mitigate potential impacts.

• Potential for code execution or unspecified impacts before certificate authentication.
• Possible overwrite of session control block pointers.
• Need for verification of server certificate authentication and TLS 1.3 configuration.
• Priority for patching and compensating controls.

Technical summary

The vulnerability exists in the TLS 1.3 handshake message cache of Eclipse ThreadX NetX Duo 6.5.1.202602. A malicious server can send a handshake message larger than the cache, causing an out-of-bounds write that can potentially overwrite pointers in the session control block. This issue can be exploited before certificate authentication completes, without requiring a server certificate. The affected product deployments should be reviewed for exposure, and defenders should verify server certificate authentication and TLS 1.3 configuration to mitigate potential impacts.

Defensive priority

High

Recommended defensive actions

• Assess exposure and prioritize patching for Eclipse ThreadX NetX Duo 6.5.1.202602 or earlier versions.
• Verify server certificate authentication and TLS 1.3 configuration.
• Monitor for suspicious TLS 1.3 handshake activity.
• Consider compensating controls, such as network segmentation or intrusion detection.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record and source item provide details on the vulnerability, including its description, CVSS score, and affected versions. However, additional information on exploitation, impact, and remediation is limited.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.