CVE-2026-66279

Description

In Connect SDK 4.3.1 and earlier and Flex SDK 3.7.7 and earlier, a message with invalid security settings may bypass authentication resulting in network disruption. This vulnerability does not allow an attacker to gain the Network Key or otherwise break confidentiality.

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EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.16%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-940 CWE-940

References

Other References

https://github.com/SiliconLabsSoftware/docs-security-advisories/blob/main/Advisories/500-599/A-00000588.md https://github.com/SiliconLabsSoftware/sisdk-release/

Frequently Asked Questions

What is CVE-2026-66279? +

In Connect SDK 4.3.1 and earlier and Flex SDK 3.7.7 and earlier, a message with invalid security settings may bypass authentication resulting in network disruption. This vulnerability does not allow an attacker to gain the Network Key or otherwise break confidentiality.

How do I check if I'm vulnerable to CVE-2026-66279? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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