CVE-2009-4444
6.0CVSSMEDIUM
Description
Microsoft Internet Information Services (IIS) 5.x and 6.x uses only the portion of a filename before a ; (semicolon) character to determine the file extension, which allows remote attackers to bypass intended extension restrictions of third-party upload applications via a filename with a (1) .asp, (2) .cer, or (3) .asa first extension, followed by a semicolon and a safe extension, as demonstrated by the use of asp.dll to handle a .asp;.jpg file.
CVSS Vector Breakdown
Exploitability
AV:NAccess VectorNetwork
AC:MAccess ComplexityMedium
Au:SAuthenticationSingle
Impact
C:PConfidentialityPartial
I:PIntegrityPartial
A:PAvailabilityPartial
Weaknesses
Affected Products
Exploitability
No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
References
http://www.securityfocus.com/bid/37460
securityfocus.com
http://securitytracker.com/id?1023387
securitytracker.com
http://blogs.technet.com/msrc/archive/2009/12/27/new-reports-of-a-vulnerability-in-iis.aspx
blogs.technet.com
and 3 more references View all →
Timeline
Published
Dec 29, 2009
Last Updated
Apr 23, 2026
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