How severe is CVE-2009-1122?

CVE-2009-1122 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2009-1122 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 98% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-1122?

CVE-2009-1122 affects Microsoft Internet Information Services. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-1122?

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

When was CVE-2009-1122 published?

CVE-2009-1122 was published on 2009-06-10 and last updated on 2026-06-16.

CVE-2009-1122

CVE-2009-1122 is a high-severity vulnerability in Microsoft Internet Information Services with a CVSS 2.0 base score of 7.5. Its EPSS exploit-prediction score of 98% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 2.0 base score 7.5)
EPSS exploit prediction: 98% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Microsoft Internet Information Services
Published: 2009-06-10
Last modified: 2026-06-16

Description

The WebDAV extension in Microsoft Internet Information Services (IIS) 5.0 on Windows 2000 SP4 does not properly decode URLs, which allows remote attackers to bypass authentication, and possibly read or create files, via a crafted HTTP request, aka "IIS 5.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1535.

Frequently asked questions

What is CVE-2009-1122?: The WebDAV extension in Microsoft Internet Information Services (IIS) 5.0 on Windows 2000 SP4 does not properly decode URLs, which allows remote attackers to bypass authentication, and possibly read or create files, via a crafted HTTP request, aka "IIS 5.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1535.
How severe is CVE-2009-1122?: CVE-2009-1122 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2009-1122 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 98% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-1122?: CVE-2009-1122 affects Microsoft Internet Information Services. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-1122?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2009-1122 published?: CVE-2009-1122 was published on 2009-06-10 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:microsoft:internet_information_services:5.0:*:*:*:*:*:*:*

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