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.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Internet_information_services | Microsoft | 5.0 | 5.0 |
| Internet_information_services | Microsoft | 6.0 | 6.0 |