Microsoft Exchange Server Security Feature Bypass Vulnerability
https://www.zscaler.com/blogs/security-research/retrospective-avoslocker
https://www.cisa.gov/news-events/cybersecurity-advisories/aa23-215a
https://www.tenable.com/cyber-exposure/tenable-2022-threat-landscape-report
https://duo.com/decipher/hive-ransomware-attacks-target-fortios-microsoft-exchange-flaws
https://www.tenable.com/cyber-exposure/a-look-inside-the-ransomware-ecosystem
https://www.cisa.gov/news-events/cybersecurity-advisories/aa22-117a
https://www.tenable.com/cyber-exposure/2021-threat-landscape-retrospective
https://www.securityweek.com/babuk-ransomware-seen-exploiting-proxyshell-vulnerabilities/
https://www.zerodayinitiative.com/advisories/ZDI-21-819/
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207