Is CVE-2009-2521 in the CISA KEV catalog?

No. CVE-2009-2521 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2009-2521?

CVE-2009-2521 has a CVSS v2 base score of 5.0 (MEDIUM).

What is the EPSS score for CVE-2009-2521?

CVE-2009-2521 has an EPSS score of 82.27% (100th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2009-2521

MEDIUMEPSS 100th pctl

5.0

CVSS v2

NVD

Description

Stack consumption vulnerability in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 7.0 allows remote authenticated users to cause a denial of service (daemon crash) via a list (ls) -R command containing a wildcard that references a subdirectory, followed by a .. (dot dot), aka "IIS FTP Service DoS Vulnerability."

CWE-400Resource Exhaustion

CVSS v2 Vector

No CVSS vector data available.

Exploit Intelligence

82.27%probability of exploitation in 30 days

100thpercentile

Very high risk: more likely to be exploited than 100% of all known CVEs.

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-23.