website is crashing

Site becomes down and I go the following error message :

I had to disable the extension to put my website back online !

Une erreur de type E_ERROR a été causée dans la ligne 63 du fichier /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Scanner/HeuristicAnalyser/Modules/Entropy.php. Message d’erreur : Uncaught RuntimeException: Index invalid or out of range in /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Scanner/HeuristicAnalyser/Modules/Entropy.php:63
Stack trace: 0 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Scanner/HeuristicAnalyser/HeuristicAnalyser.php(377): CleantalkSP\Common\Scanner\HeuristicAnalyser\Modules\Entropy->analyse() 1 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Scanner/HeuristicAnalyser/Controller.php(55): CleantalkSP\Common\Scanner\HeuristicAnalyser\HeuristicAnalyser->processContent() 2 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Scanner/HeuristicAnalyser/Controller.php(26): CleantalkSP\Common\Scanner\HeuristicAnalyser\Controller->scanFileForHeuristic() 3 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/ScannerQueue.php(1350): CleantalkSP\Common\Scanner\HeuristicAnalyser\Controller->scanFile() 4 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/ScannerQueue.php(186): CleantalkSP\SpbctWP\Scanner\ScannerQueue->heuristic_analysis() 5 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/inc/spbc-scanner.php(49): CleantalkSP\SpbctWP\Scanner\ScannerQueue::controllerBackground() 6 [internal function]: spbc_scanner__controller() 7 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Cron.php(121): call_user_func_array() 8 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Cron.php(54): CleantalkSP\Common\Cron->runTasks() 9 /rfstockage.fr/public_html/wp-content/plugins/security-malware-firewall/security-malware-firewall.php(295): CleantalkSP\Common\Cron->execute() 10 /rfstockage.fr/public_html/wp-settings.php(462): include_once(‘/home/u24292041…’) 11 /rfstockage.fr/public_html/wp-config.php(95): require_once(‘/home/u24292041…’) 12 /rfstockage.fr/public_html/wp-load.php(50): require_once(‘/home/u24292041…’) 13 /rfstockage.fr/public_html/wp-login.php(12): require(‘/home/u24292041…’) 14 {main}

  thrown

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