CVE-2009-2521Stack consumption vulnerability in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 7.0 allows remote…
- 5.0MediumCVSS base score
- 82.3%Exploitation in 30 daysEPSS · top 0.3% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- 3Public exploitsMetasploit, Nuclei and Exploit-DB
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."
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list a Metasploit module and 2 Exploit-DB entries for it.
Show the exploits3
Metasploit modules1 module
- Microsoft IIS FTP Server LIST Stack Exhaustion (Metasploit module) (opens in a new tab)
auxiliary/dos/windows/ftp/iis_list_exhaustionRank normaldisclosed 3 Sept 2009
Exploit-DB2 entries
- Microsoft IIS 7.0 FTP Server - Stack Exhaustion Denial of Service (MS09-053) (Metasploit) (Exploit-DB entry) (opens in a new tab)
EDB-ID 17476dos, windowspublished 3 Jul 2011Not verified
- Microsoft IIS 5.0/6.0 FTP Server - Stack Exhaustion Denial of Service (Exploit-DB entry) (opens in a new tab)
EDB-ID 9587dos, windowspublished 4 Sept 2009Verified
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By microsoft
- 49 days later
· 49 days later
Published
- 15 years later
· 15 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Medium5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
- EPSS (exploitation in 30 days)
- 82.3% · top 0.3% of all CVEs (15 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.0.
Affected products
n/a
- affected n/a
References
References5
- oval:org.mitre.oval:def:6508 (opens in a new tab)vdb-entrysignaturex_refsource_OVALx_transferred
- 975191 (opens in a new tab)vendor-advisoryx_refsource_MSKBx_transferred
- TA09-286A (opens in a new tab)third-party-advisoryx_refsource_CERTx_transferred
- MS09-053 (opens in a new tab)vendor-advisoryx_refsource_MSx_transferred
- 20090903 Microsoft Internet Information Services 5.0/6.0 FTP SERVER DENIAL OF SERVICE ("Stack Exhaustion") (opens in a new tab)mailing-listx_refsource_FULLDISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2009-2516 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2009-2521)Record last updated .