SSTI Attack Guide 2026: Server-Side Template Injection Detection, Exploitation & Bypass
Server-Side Template Injection (SSTI) is one of the most dangerous web vulnerabilities you’ll encounter. A simple {{7*7}} in the right field can hand you full remote code execution on a production server. This guide covers everything — detection, fingerprinting, exploitation, WAF bypass, and defense — for every major template engine in 2026. What Is SSTI? Web frameworks use template engines to render dynamic content — think Flask with Jinja2, PHP apps with Twig, Java apps with FreeMarker. When user input is concatenated directly into a template string rather than passed as a variable, the template engine evaluates it. That’s SSTI. ...