Sitecore XP 7.5 Initial Release to Sitecore XP 8.2 Update-7 is vulnerable to an insecure deserialization attack where it is possible to achieve remote command execution on the machine. No authentication or special configuration is required to exploit this vulnerability.
https://veriti.ai/blog/vulnerable-villain-when-hackers-get-hacked/
https://www.secureworks.com/research/gold-melody-profile-of-an-initial-access-broker?&web_view=true
https://www.cisa.gov/news-events/cybersecurity-advisories/aa22-117a
https://support.sitecore.com/kb?id=kb_article_view&sysparm_article=KB1000776