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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.24%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 4.0
- 7.2 HIGHCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/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/M
- EPSS
- 0.24% probability · 16th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-940
- Source
- product-security@silabs.com
EPSS moved from 0.2% on 23 October 2026 to 0.2% on 26 October 2026.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.