Critical Exchange Server Flaw (CVE-2024-21410) Under Active Exploitation

Microsoft confirmed active exploitation of CVE-2024-21410, a critical (CVSS 9.8) Exchange Server privilege-escalation bug that can leak NTLM credentials and allow attackers to relay Net-NTLMv2 hashes to authenticate as users; fixes were issued and Microsoft set the Exploitability Assessment to "Exploitation Detected" and enabled Extended Protection for Authentication by default in recent updates. The report places this flaw alongside other recently patched, actively weaponized issues (CVE-2024-21351, CVE-2024-21412, CVE-2024-21413) and highlights potential abuse by state-affiliated actors like APT28 and Water Hydra.