cve 2026 45501

CVE-2026-45501 is an Important-rated Microsoft Exchange Server spoofing vulnerability disclosed in Microsoft’s June 9, 2026 security updates. It affects on-premises Exchange Server and is part of a broader patch set that also includes fixes for spoofing, information-disclosure, privilege-escalation, and remote-code-execution vulnerabilities. The advisory provides limited detail, requiring administrators to rely on sparse guidance when making patching decisions. This tag covers discussions around the vulnerability, its impact, and recommended action steps for enterprise IT teams managing Exchange environments.