How severe is CVE-2011-1966?

CVE-2011-1966 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2011-1966 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 55% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-1966?

CVE-2011-1966 primarily affects Microsoft Windows Server 2008. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-1966?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2011-1966 published?

CVE-2011-1966 was published on 2011-08-10 and last updated on 2026-06-16.

CVE-2011-1966

CVE-2011-1966 is a critical-severity vulnerability in Microsoft Windows Server 2008 with a CVSS 2.0 base score of 10.0. Its EPSS exploit-prediction score of 55% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 55% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Windows Server 2008
Published: 2011-08-10
Last modified: 2026-06-16

Description

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."

Frequently asked questions

What is 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."
How severe is CVE-2011-1966?: CVE-2011-1966 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2011-1966 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 55% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-1966?: CVE-2011-1966 primarily affects Microsoft Windows Server 2008. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-1966?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2011-1966 published?: CVE-2011-1966 was published on 2011-08-10 and last updated on 2026-06-16.

References

Affected products (3)

cpe:2.3:o:microsoft:windows_server_2008:*:sp2:x32:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:*:sp2:x64:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:r2:*:x64:*:*:*:*:*

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