CVE-2026-21243 HIGH

CVE-2026-21243: Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability

Vendor Microsoft
Product Windows Server 2019
Weakness CWE-476
Published February 10, 2026
Last update May 11, 2026
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

What the vulnerability does

01Description

Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.

Key dates

02Disclosure timeline

February 10, 2026 CVE published
May 11, 2026 Record updated