CVE-2026-21243

CWE-476 — NULL Pointer Dereference5 documents5 sources
Severity
7.5HIGH
EPSS
0.1%
top 75.18%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
6
Microsoft Windows Server 2019Microsoft Windows Server 2019 (server Core Installation)Microsoft Windows Server 2022+3 more
Timeline
PublishedFeb 10

Description

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

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 3.9 | Impact: 3.6

Affected Packages6 packages

▶NVDmicrosoft/windows< 10.0.17763.8389+3
▶CVEListV5microsoft/windows_server_201910.0.17763.0 — 10.0.17763.8389
▶CVEListV5microsoft/windows_server_202210.0.20348.0 — 10.0.20348.4773
▶CVEListV5microsoft/windows_server_202510.0.26100.0 — 10.0.26100.32370
▶CVEListV5microsoft/windows_server_2019_(server_core_installation)10.0.17763.0 — 10.0.17763.8389

🔴Vulnerability Details

2
GHSA
GHSA-843x-gmwc-22g8: Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network↗2026-02-10
▶
CVEList
Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability↗2026-02-10
▶

📋Vendor Advisories

1
Microsoft
Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability↗2026-02-10
▶

🕵️Threat Intelligence

1
Wiz
CVE-2026-21243 Impact, Exploitability, and Mitigation Steps | Wiz↗
▶
CVE-2026-21243 (HIGH CVSS 7.5) | Null pointer dereference in Windows | cvebase.io