Which products and versions are affected by CVE-2011-1966?

Affected: Windows Server 2008 (Microsoft) versions r2. The full list is in the CVE brief.

Is CVE-2011-1966 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2011-1966 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2011-1966?

No public exploit code is known.

Is there a fix for CVE-2011-1966?

No fixed version is listed yet; check the vendor advisory for mitigations.

How urgently should CVE-2011-1966 be patched?

Brandefense priority: patch immediately, because it is very likely to be exploited soon.

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Vulnerability Intelligence

CVE-2011-1966

Critical

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 Aug 10, 2011 · Updated Apr 28, 2026

Key Facts

Patch immediately

CVE-2011-1966 is a critical-severity vulnerability (CVSS 10.0 v2) affecting Windows Server 2008 (Microsoft).
It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
EPSS estimates a 55% probability of exploitation in the next 30 days.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

CVSS v2

10.0

AV:N/AC:L/Au:N/C:C/I:C/A:C

EPSS (30-day exploit likelihood)

55%

Higher than 99.0% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

None known

Get the full CVE-2011-1966 brief as a PDF

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Description

Affected Products

3 affected entries in total

Product	Affected versions	Fixed in
Windows Server 2008Microsoft	r2	n/a

Timeline

Publicly disclosed
Aug 10, 2011
Last updated
Apr 28, 2026

Weakness Type

CWE-20 Improper Input Validation

References

FAQ

Common Questions.

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."
Affected: Windows Server 2008 (Microsoft) versions r2. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

Is CVE-2011-1966 Running On Your Attack Surface?

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