Nuclei
Project Discovery vulnerability scanner
About this crawler
Nuclei is a web crawler identified by the regular-expression pattern Nuclei in the User-Agent request header. It is categorised as scanner. Use the regex above to detect, log, allow, or block Nuclei traffic in your web server, CDN edge rules, or robots.txt.
Block-rate · top 25k sites
0.46%
Technical details
- Name
- Nuclei
- Pattern
Nuclei- Tags
- scanner
- Reference
- https://projectdiscovery.io/nuclei/
- Added
- 2026/05/09
- Instances
- 1 known sample(s)
Sample User-Agent strings
Nuclei (@pdiscoveryio)
Block this crawler
robots.txt — disallow Nuclei:
User-agent: Nuclei
Disallow: /
Apache .htaccess — return 403:
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} Nuclei [NC]
RewriteRule .* - [F,L]
Nginx — return 403 inside a server block:
if ($http_user_agent ~* "Nuclei") {
return 403;
}
← back to all crawlers