CVE-2021-20039

Improper neutralization of special elements in the SMA100 management interface '/cgi-bin/viewcert' POST http method allows a remote authenticated attacker to inject arbitrary commands as a 'nobody' user. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.

• CWE-78
• CWE-78

• http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authenticated-Command-Injection.htmlExploit, Third Party Advisory, VDB Entry
• https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026Vendor Advisory
• http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authenticated-Command-Injection.htmlExploit, Third Party Advisory, VDB Entry
• https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026Vendor Advisory
• https://attackerkb.com/topics/9szJhq46lw/cve-2021-20039/rapid7-analysis

Published

Dec 8, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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