The impacted devices include the SMA 200, 210, 400, 410, and 500 edge network access control systems that have the Web Application Firewall (WAF) enabled.

The most severe of these vulnerabilities is CVE-2021-20038 (CVSS score of 9.8), an unauthenticated stack-based buffer overflow that could lead to remote code execution (RCE) as the ‘nobody’ user.

“The vulnerability is due to the SonicWall SMA SSLVPN Apache httpd server GET method of mod_cgi module environment variables use a single stack-based buffer using `strcat`. This allows remote attacker to cause stack-based buffer overflow and would result in code execution,” SonicWall says.