Web application firewallA managed WAF that stops attacks at the edge.
SQL injection, cross-site scripting, path traversal and command injection are inspected and blocked before a request reaches your server. nsin keeps the rules current; you only choose where and how strict.
Managed, on the OWASP Core Rule Set
You do not write signatures. The firewall runs the OWASP Core Rule Set and nsin maintains it. Add a WAF rule for the whole site, or a stricter one for an admin area or an API.
- SQL injection, XSS, path traversal, command injection
- Scope by path and by hostname
- Inspection happens at the edge, in milliseconds
Tune how strict it is
Strictness sets how many checks run, from clear attacks only to subtle ones. Sensitivity sets the score at which a request is blocked. A body inspection limit keeps large uploads fast.
- Four strictness levels
- Adjustable blocking threshold
- Body inspection limit per rule
Dry run before you enforce
A rule in dry run logs what it would have blocked and lets everything through. Read the WAF log for a day or two, exclude the one check that caught real traffic, then enforce.
- WAF log names the exact check that matched
- Exclude a single rule id instead of weakening the rest
- Combine with rate limiting and block rules
Frequently asked questions
What does a WAF protect against?
Attacks hidden inside otherwise normal requests: SQL injection, cross-site scripting, path traversal and command injection. It does not replace rate limiting or DDoS protection, which nsin provides separately.
Will the WAF block real visitors?
Start in dry run. If the WAF log shows real traffic matching a check, exclude that rule id or narrow the paths. Everything else keeps protecting the site.
Does the WAF slow my site down?
No. Inspection runs at the edge in milliseconds, and the body inspection limit keeps large uploads from being scanned in full.
Do I need to change my application?
No. The WAF sits in front of your server. You switch it on with a rule in the panel; there is nothing to install.