Instituto Nacional de ciberseguridad. Sección Incibe
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CVE-2026-21243

Severity CVSS v4.0:
Pending analysis
Type:
CWE-476 NULL Pointer Dereference
Publication date:
10/02/2026
Last modified:
11/02/2026

Description

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

Impact

Vector 3.x
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High

Base Score 3.x
7.50
Severity 3.x
HIGH

Vulnerable products and versions

CPE From Up to
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* 10.0.17763.8389 (excluding)
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* 10.0.20348.4711 (excluding)
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:* 10.0.25398.2149 (excluding)
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* 10.0.26100.32313 (excluding)

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools