Use subpar regex validation on LEAK_FILE

modules/exploits/linux/http/cisco_ucs_cloupia_script_rce.rb

@@ -91,7 +91,9 @@ class MetasploitModule < Msf::Exploit::Remote
         [
           true,
           'Leak API key from this file (absolute path)',
-          '/opt/infra/idaccessmgr/logfile.txt'
+          '/opt/infra/idaccessmgr/logfile.txt',
+          nil, # enums
+          %r{^/.+$} # LEAK_FILE must be an absolute path
         ]
       )
     ])
@@ -118,10 +120,6 @@ class MetasploitModule < Msf::Exploit::Remote
   end
 
   def exploit
-    unless datastore['LEAK_FILE'].start_with?('/')
-      fail_with(Failure::BadConfig, 'LEAK_FILE is not an absolute path')
-    end
-
     # Randomly named file is never written to the exports directory
     create_exports_dir(
       '/opt/infra/web_cloudmgr/apache-tomcat/webapps/app/cloudmgr/exports',