CVE-2026-42897: Critical (CVSS 8.1), Actively Exploited (CISA KEV)

Critical (CVSS 8.1), Actively Exploited (CISA KEV), EPSS 5.6%.
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.