VULNERABILITY INTELLIGENCE

CVE-2009-4444

CVSS score6 MEDIUM
EPSS probability63.63%
CISA KEVNot currently listed
Published2009-12-29
Last modified2026-06-16
CVSS vectorAV:N/AC:M/Au:S/C:P/I:P/A:P

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.

Primary references