The setRequestHeader method of the XMLHttpRequest object in Microsoft Internet Explorer 7 does not restrict the dangerous Transfer-Encoding HTTP request header, which allows remote attackers to conduct HTTP request splitting and HTTP request smuggling attacks via a POST containing a "Transfer-Encoding: chunked" header and a request body with an incorrect chunk size.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.