CGI versions before 5.00 for Perl allow memory, CPU and disk exhaustion via missing or unenforced request size, parameter and upload limits.
$CGI::POST_MAX defaults to no limit, and when set is not enforced for chunked multipart bodies or for the boundary line of a multipart body without a boundary= parameter. Bodies saved as PUTDATA, POSTDATA or PATCHDATA uploads are read into memory in one go, and nothing limits the number of parameters or uploads.
Allocation of Resources Without Limits or Throttling The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.