RDP privilege escalation and session hijacking

Vuls: VULnerability Scanner

https://imagetragick.com/

https://linode.com/docs/security/meltdown-and-spectre/

https://habr.com/ru/post/455598/ - Exim RCE as root (description - http://www.opennet.ru/opennews/art.shtml?num=50819)

snort

http://www.aboutdebian.com/snort.htm

https://www.rivy.org/technologies/snort/

Intrusion Detection with Snort - Google Books

https://openmaniak.com/snort.php

scanners for PHP

https://github.com/scr34m/php-malware-scanner

https://malware.expert/malware-scanner-and-removal/

Scan your server for PHP malware with findcrack0r.pl

https://www.abuseat.org/findbot.pl

https://github.com/InterGenStudios/exBOMBER