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CVE-2009-2521

Published: Sep 4, 2009Updated: Apr 23, 2026 Sources: CVE List NVD BDUCWE-400
NVD MITRE
5.0CVSSMEDIUM
EPSS Score
82.3%
Top 0.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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."

CVSS Vector Breakdown

AV:NAC:LAu:NC:NI:NA:P
Exploitability
AV:NAccess Vector
Network
AC:LAccess Complexity
Low
Au:NAuthentication
None
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:PAvailability
Partial
Open in CVSS calculator →

Weaknesses

CWE-400

Affected Products

Microsoft Internet Information ServicesMicrosoft Corp
On-prem
Operating Systems / windows
XP-8741-AtomICP DAS Co. Ltd.
Embedded
ICS / OT / IoT / plc-scada-hmi
n/an/a
internet information servicesmicrosoft
On-premWeb App
Web & CMS Plugins / cms-core
microsoft corpcommercialUSOperating Systemsaka microsoft corporation
icp das co. ltd.commercialICS / OT / IoT
microsoftcommercialUSOperating Systems

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-2521
cve.mitre.org
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6508
oval.cisecurity.org
http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ975191
support.microsoft.com
and 3 more references View all →

Timeline

Published
Sep 4, 2009
Last Updated
Apr 23, 2026

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