CVE-2026-55008: Microsoft Exchange Server

Critical severity, CVSS 9.6. EPSS: 0.9% chance of exploitation in the next 30 days.

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.

Affected products

• Microsoft Exchange Server: version 2016 only; version 2019 only
• Microsoft Exchange Server Subscription Edition: before 15.02.2562.045 (fixed in 15.02.2562.045)

Published 2026-07-14. Last modified 2026-07-24.