CVE-2026-55008

CRITICAL

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.

CVSS v3.1 Score

9.6
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Published: 7/14/2026Modified: 7/15/2026

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NVD CRITICAL: CVE-2026-55008 — Improper neutralization of input during web page generation ('cross-site scripti...

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.

CVE-2026-55008
NIST NVD

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55008