If you notice newly created files and one of them is accesson.php, then it is highly likely that your site is infected with malware.
To restore a clean site version, you may follow the steps described here:
https://guides.magefix.com/2021/06/clean-driverfortnigtly-malware/
Try our Free site check.
Malicious logs associated with accesson.php.
46.97.198.136 – – [09/Jul/2021:21:56:13 +0000] “GET /style.php?sig=shell519&file_name=accesson.php&domain=gutsevich.ru&shell_file=accesson20 HTTP/1.1” 403 358 “https://.com/” “Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:48.0) Gecko/20100101 Firefox/48.0” .com 162.241.85.120
46.97.198.136 – – [09/Jul/2021:21:56:15 +0000] “GET /accesson.php HTTP/1.1” 403 358 “https://.com/style.php?sig=shell519&file_name=accesson.php&domain=gutsevich.ru&shell_file=accesson20” “Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:48.0) Gecko/20100101 Firefox/48.0” .com
Malicious domains: gutsevich.ru.
Malicious IPs: 188.225.40.162