Vulnerability · CVE-2009-3023
Microsoft Internet Information Services (IIS) Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Published Oct 19, 2009 · catalog updated Oct 19, 2009 · Microsoft Internet Information Services (IIS)
Patch now
CVE-2009-3023 is in the CISA known-exploited catalog. Confirm Microsoft Internet Information Services (IIS) against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- Unknown—
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 90.91%
- Remediation
- Remediation guidance
- Affected products
- vendor Microsoft Internet Information Services (IIS)
Buffer overflow in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 6.0 allows remote authenticated users to execute arbitrary code via a crafted NLST (NAME LIST) command that uses wildcards, leading to memory corruption, aka "IIS FTP Service RCE and DoS Vulnerability."
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor Microsoft Internet Information Services (IIS)version unspecified
How to fix CVE-2009-3023
Recommended remediation
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2009-3023 is in the CISA known-exploited catalog. Confirm Microsoft Internet Information Services (IIS) against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
What should an analyst verify?
No weakness class is stored. EPSS 90.91%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Oct 19, 2009 · VulnCheck KEV
Detected
Buffer overflow in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 6.0 allows remote authenticated users to execute arbitrary code via a crafted NLST (NAME LIST) command that uses wildcards, leading to memory corruption, aka "IIS FTP Service RCE and DoS Vulnerability."
Oct 19, 2009 · CISA KEV
Known exploited
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Sources
- CVE.orgVulnerability recordCVE-2009-3023
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2009-3023
30-day exploitation probability 90.9%
first.org - VulnCheck KEVConfirmed exploitationCVE-2009-3023
Buffer overflow in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 6.0 allows remote authenticated users to execute arbitrary code via a crafted NLST (NAME LIST) command that uses wildcards, leading to memory corruption, aka "IIS FTP Service RCE and D
vulncheck.com
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.