How severe is CVE-2011-0040?

CVE-2011-0040 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2011-0040 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 23% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-0040?

CVE-2011-0040 primarily affects Microsoft Windows 2003 Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-0040?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2011-0040 published?

CVE-2011-0040 was published on 2011-02-09 and last updated on 2026-06-16.

CVE-2011-0040

CVE-2011-0040 is a medium-severity vulnerability in Microsoft Windows 2003 Server with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 23% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 23% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Windows 2003 Server
Published: 2011-02-09
Last modified: 2026-06-16

Description

The server in Microsoft Active Directory on Windows Server 2003 SP2 does not properly handle an update request for a service principal name (SPN), which allows remote attackers to cause a denial of service (authentication downgrade or outage) via a crafted request that triggers name collisions, aka "Active Directory SPN Validation Vulnerability."

Frequently asked questions

What is CVE-2011-0040?: The server in Microsoft Active Directory on Windows Server 2003 SP2 does not properly handle an update request for a service principal name (SPN), which allows remote attackers to cause a denial of service (authentication downgrade or outage) via a crafted request that triggers name collisions, aka "Active Directory SPN Validation Vulnerability."
How severe is CVE-2011-0040?: CVE-2011-0040 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2011-0040 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 23% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-0040?: CVE-2011-0040 primarily affects Microsoft Windows 2003 Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-0040?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-0040 published?: CVE-2011-0040 was published on 2011-02-09 and last updated on 2026-06-16.

References

Affected products (3)

cpe:2.3:o:microsoft:windows_2003_server:*:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_2003_server:*:sp2:itanium:*:*:*:*:*
cpe:2.3:o:microsoft:windows_2003_server:*:sp2:x64:*:*:*:*:*

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