CVE-2026-21243 (GCVE-0-2026-21243)

Vulnerability from cvelistv5 – Published: 2026-02-10 17:51 – Updated: 2026-08-19 16:26
VLAI
Title
Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability
Summary
Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.
Severity
7.5 (High)
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
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-11 15:27 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
Vendor Product Version CPE status
Microsoft Windows Server 2019 Affected: 10.0.17763.0 , < 10.0.17763.8389 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2019 (Server Core installation) Affected: 10.0.17763.0 , < 10.0.17763.8389 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2022 Affected: 10.0.20348.0 , < 10.0.20348.4773 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) Affected: 10.0.25398.0 , < 10.0.25398.2149 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2025 Affected: 10.0.26100.0 , < 10.0.26100.32370 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2025 (Server Core installation) Affected: 10.0.26100.0 , < 10.0.26100.32370 (custom)
guessed Create a notification for this product.
Date Public
2026-02-10 16:00
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.