Which products and versions are affected by CVE-2009-3023?

Affected: Internet Information Server (Microsoft). The full list is in the CVE brief.

Is CVE-2009-3023 being exploited in the wild?

It is exploited in the wild, listed in Industry KEV feed since Oct 19, 2009.

Is CVE-2009-3023 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2009-3023?

Public exploit code is available.

Is there a fix for CVE-2009-3023?

Fixed versions are available, including Internet Information Server 6.0.

How urgently should CVE-2009-3023 be patched?

Brandefense priority: patch immediately, because it is listed as exploited in the wild.

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Vulnerability Intelligence

CVE-2009-3023

CriticalExploitedPublic exploit

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…

Published Aug 31, 2009 · Updated Apr 22, 2026

Key Facts

Patch immediately

CVE-2009-3023 is a critical-severity vulnerability (CVSS 9.0 v2) affecting Internet Information Server (Microsoft).
It is exploited in the wild, listed in Industry KEV feed since Oct 19, 2009. Public exploit code is available.
EPSS estimates a 91% probability of exploitation in the next 30 days.
Fixed versions are available, including Internet Information Server 6.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v2

9.0

AV:N/AC:L/Au:S/C:C/I:C/A:C

EPSS (30-day exploit likelihood)

91%

Higher than 99.8% of all scored CVEs

Exploited in the wild

Yes

1 catalog listing

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2009-3023 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

Known-Exploited Catalog Listings

Catalog	Added	Remediation due	Ransomware use
Industry KEV feed	Oct 19, 2009	n/a	Not reported

Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Affected Products

1 affected entries in total

Product	Affected versions	Fixed in
Internet Information ServerMicrosoft	See advisory	6.0

Patched Releases

Internet Information Server

6.0

Timeline

Publicly disclosed
Aug 31, 2009
Added to Industry KEV feed
Oct 19, 2009
Last updated
Apr 22, 2026

Weakness Type

CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

References

9 more references in the full CVE brief

FAQ

Common Questions.

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."
Affected: Internet Information Server (Microsoft). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Oct 19, 2009.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Internet Information Server 6.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

Is CVE-2009-3023 Running On Your Attack Surface?

Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.