Add lower bound version

Author: Chocapikk

modules/exploits/multi/http/invision_customcss_rce.rb

@@ -81,10 +81,10 @@ def check
     version = Rex::Version.new(Regexp.last_match(1))
     print_status("Detected IPS version: #{version}")
 
-    if version <= Rex::Version.new('5.0.6')
+    if version.between?(Rex::Version.new('5.0.0'), Rex::Version.new('5.0.6'))
       CheckCode::Vulnerable("IPS version #{version} is vulnerable (≤ 5.0.6)")
     else
-      CheckCode::Safe("IPS version #{version} appears patched (> 5.0.6)")
+      CheckCode::Safe("IPS version #{version} is not vulnerable")
     end
   end