Skip to content
Fencer Vulns
medium 5.0

CVE-2009-2521 json

Stack consumption vulnerability in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 7.0 allows remote authentic…

published 2009-09-04 17 y ago modified 2026-06-16 4 mo ago also EUVD-2009-2516

cvss
5.0
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
82.3%
EPSS 82.3% chance of exploitation in 30 days, percentile 99.6%
public exploits
3
Metasploit, Exploit-DB

Summary

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."

Patch / fix

Timeline

  1. First public exploit (Metasploit auxiliary/dos/windows/ftp/iis_list_exhaustion)
  2. Published

Exploit prediction

82.27% chance of exploitation in the next 30 days, higher than 99.6% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

CVSS scores

assigned by version score vector
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.