The history of ProxyNotShell, the Microsoft vulnerability 

ProxyNotShell is an evolved exploit chain against Microsoft Exchange (notably CVE-2022-41040 and CVE-2022-41082) that followed the earlier ProxyShell flaws; it enables SSRF leading to remote code execution, was observed in limited targeted attacks, has had mitigations bypassed (OWASSRF), left many internet-facing Exchange instances vulnerable, and highlights the need for immediate patching and layered defensive measures.