CVE-2011-1966

The DNS server in Microsoft Windows Server 2008 SP2, R2, and R2 SP1 does not properly handle NAPTR queries that trigger recursive processing, which allows remote attackers to execute arbitrary code via a crafted query, aka "DNS NAPTR Query Vulnerability."

Published: 2011-08-10 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2011-1966 is rated High Risk (73.1/100): CVSS Critical severity, with high exploitation likelihood (EPSS 57.19%, 98th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2011-1966

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-09 58.37% 57.19% -1.18%
2 2026-01-03 57.66% 58.37% +0.70%
3 2025-10-18 57.66%

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2011-1966

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
10.0 10.0 [email protected]

Weakness enumeration for CVE-2011-1966

Affected software / configurations for CVE-2011-1966

Vendor Product Version Raw CPE
microsoft windows_server_2008 cpe:2.3:o:microsoft:windows_server_2008:*:sp2:x32:*:*:*:*:*
microsoft windows_server_2008 cpe:2.3:o:microsoft:windows_server_2008:*:sp2:x64:*:*:*:*:*
microsoft windows_server_2008 r2 cpe:2.3:o:microsoft:windows_server_2008:r2:*:x64:*:*:*:*:*

References for CVE-2011-1966

cvelogic Threat Intelligence