CVE-2021-42342: Embedthis GoAhead

Critical severity, CVSS 9.8. EPSS: 59.5% chance of exploitation in the next 30 days.

An issue was discovered in GoAhead 4.x and 5.x before 5.1.5. In the file upload filter, user form variables can be passed to CGI scripts without being prefixed with the CGI prefix. This permits tunneling untrusted environment variables into vulnerable CGI scripts.

Affected products

• Embedthis GoAhead: from 4.0.0, up to and including 4.1.3; from 5.0.0, before 5.1.5 (fixed in 5.1.5)

Published 2021-10-14. Last modified 2026-06-17.