CVE-2023-21816
Published: 14 February 2023
Summary
CVE-2023-21816 is a high-severity Improper Input Validation (CWE-20) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 5.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
Windows Active Directory Domain Services API contains a denial-of-service vulnerability tracked as CVE-2023-21816. The flaw is present in the Active Directory Domain Services component of supported Windows Server releases and carries a CVSS 3.1 base score of 7.5, reflecting network attack vector, low attack complexity, and no required privileges or user interaction, with high impact on availability.
An unauthenticated remote attacker can send specially crafted requests to an affected domain controller, triggering the vulnerability and causing the Active Directory Domain Services API to stop responding. Successful exploitation results in a denial-of-service condition that disrupts authentication and directory operations for domain-joined systems without allowing data disclosure or integrity changes.
Microsoft’s Security Response Center advisory for CVE-2023-21816 directs administrators to apply the security updates released on the February 2023 Patch Tuesday, which address the input-validation issue underlying the flaw. The EPSS score reached a peak of 0.2072 and currently stands at 0.1636, indicating moderate but not sharply rising exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-25982
Vulnerability details
Windows Active Directory Domain Services API Denial of Service Vulnerability
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.
Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.
Directly implements checks on information inputs to reject invalid data before processing.
Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.