Authentication Bypass Vulnerability in Connect SDK and Flex SDK by Silicon Labs
CVE-2026-66279

7.2HIGH

Key Information:

Vendor

Silicon Labs

Status
Connect Sdk
Vendor
CVE Published:
22 October 2026

What is CVE-2026-66279?

In certain versions of Connect SDK and Flex SDK, an attacker can exploit a weakness in the handling of security settings, allowing messages with invalid configurations to bypass required authentication checks. This compromise may lead to disruptions in network operations, although it does not permit access to sensitive data such as the Network Key. Users are strongly urged to update to the patched versions to mitigate this risk.

Affected Version(s)

Connect SDK 4.0.0 <= 4.3.1

Connect SDK 0 <= 3.7.7

References

https://github.com/SiliconLabsSoftware/docs-security-advi...
vendor-advisorypermissions-required
https://github.com/SiliconLabsSoftware/sisdk-release/
patch

CVSS V4

Score:
7.2
Severity:
HIGH
Confidentiality:
None
Integrity:
High
Availability:
High
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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