CVE-2009-4444
mediumpriority · attend · 46EPSS 0.636 · 99 %ileEUUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
- microsoft internet information services= 5.0nvdUScpe:2.3:a:microsoft:internet_information_services:*:*:*:*:*:*:*:*
- microsoft internet information services= 6.0nvdUScpe:2.3:a:microsoft:internet_information_services:*:*:*:*:*:*:*:*
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (12)
External citations — patches, advisories, analysis.
- http://blogs.technet.com/msrc/archive/2009/12/27/new-reports-of-a-vulnerability-in-iis.aspxenisa_euvd
- http://secunia.com/advisories/37831enisa_euvd
- http://securitytracker.com/id?1023387enisa_euvd
- http://soroush.secproject.com/downloadable/iis-semicolon-report.pdfenisa_euvd
- http://www.securityfocus.com/bid/37460enisa_euvd
- http://www.vupen.com/english/advisories/2009/3634enisa_euvd
- http://blogs.technet.com/msrc/archive/2009/12/27/new-reports-of-a-vulnerability-in-iis.aspxBroken Linknvd
- http://secunia.com/advisories/37831Third Party Advisorynvd
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