NetComm NF20MESH routers running firmware R6B031 and earlier contain an authentication bypass vulnerability that allows unauthenticated attackers to gain administrative access by exploiting a hardcoded AES-256 key used to encrypt session cookies for the web management interface. Attackers can forge a valid encrypted session cookie using the shared hardcoded key and bypass authentication checks to obtain full administrative control of the management interface while any legitimate administrator session is active.
https://www.vulncheck.com/advisories/netcomm-nf20mesh-r6b032-hardcoded-aes-key-authentication-bypass
https://support.netcommwireless.com/products/nf20mesh#Firmware
https://signal11.io/advisories/netcomm-nf20-mesh-authentication-bypass
Published: 2026-06-23
Updated: 2026-06-23
Base Score: 7.6
Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 8.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 9.2
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: Critical
EPSS: 0.00431