CVE-2026-21243: high-severity vulnerability in Microsoft Windows Server 2019
Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 1.4%
Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.
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
Affected products
Microsoft · Windows Server 2019Microsoft · Windows Server 2019 (Server Core installation)Microsoft · Windows Server 2022Microsoft · Windows Server 2022, 23H2 Edition (Server Core installation)Microsoft · Windows Server 2025Microsoft · Windows Server 2025 (Server Core installation)Related CVEs — Microsoft Windows Server 2019
In the same product, most dangerous first.
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