Unrestricted file upload vulnerability in Collabtive 0.4.8 allows remote authenticated users to execute arbitrary code by uploading a file with an executable extension and using a text/plain MIME type, then accessing it via a direct request to the file in files/, related to (1) the showproject action in managefile.php or (2) the Messages feature.
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.