CVE-2026-56191: CRITICAL improper authentication in Microsoft Exchange Online (CVSS 10). Remote, unauthenticated attackers can tamper with systems. Official fix available — patch ASAP. Details: https://radar.offseq.com/threat/cve-2026-56191-cwe-287-improper-authentication-in-microsoft-microsoft-exchange-online-2fb5560625ca8222 #OffSeq #CVE202656191 #ExchangeOnline #Vuln