CVE-2009-2521

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 82.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2009-09-04 · updated 2026-06-16
Weakness: CWE-400

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."

Affected products

Microsoft IIS: from 5.0 through 7.0

References

http://archives.neohapsis.com/archives/fulldisclosure/2009-09/0040.html
http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ975191
http://www.us-cert.gov/cas/techalerts/TA09-286A.html
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-053
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6508
http://archives.neohapsis.com/archives/fulldisclosure/2009-09/0040.html
http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ975191
http://www.us-cert.gov/cas/techalerts/TA09-286A.html
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-053
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6508

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