CVE-2026-66279: CWE-940: Improper Verification of Source of a Communication Channel in Silicon Labs Connect SDK
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.
CVSS v4.0
Score 7.2high
Affected software
Silicon Labs
Connect SDK
pkg:github/Connect SDKRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability identified as CVE-2026-66279 affects Silicon Labs Connect SDK versions 4.0.0 through 4.3.1 and Flex SDK versions up to 3.7.7. It is classified under CWE-940, which concerns improper verification of the source of a communication channel. Due to this flaw, messages that do not meet proper security settings may bypass authentication mechanisms, leading to network disruption. However, the vulnerability does not allow attackers to extract the Network Key or break confidentiality of communications.
Potential Impact
An attacker can send messages with invalid security settings that bypass authentication, resulting in disruption of network operations. There is no impact on confidentiality as the Network Key and sensitive data remain protected.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, monitor for unusual network disruptions and consider applying any vendor recommendations once published.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Silabs
- Date Reserved
- 2026-07-24T13:33:53.357Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ada17294d27ba8daa5b44b4
Added to database: 10/22/2026, 14:01:13 UTC
Last enriched: 10/22/2026, 14:15:24 UTC
Last updated: 10/22/2026, 17:15:45 UTC
Views: 9
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.