Why is the Reject Attachments option not rejecting all of the set attachment types?
I have set the Juce > Reject Attachments option to reject a number of particular file types from entering my server. Some of these file types are getting through while others with the exact same exxtension are being successfully blocked.
We have made a hotfix available on our public ftp site for this issue.
The problem was being caused by the formating of the mime headers of the message which had been specially constructed in an attempt to fool Anti-Virus and Content Scanning software. This caused the Attachment rejection mechanism to not find the correct extension for the attachment in question. An example of such mime content follows:
Content-type: application/octet-stream; name=Colour Digital Camera VP.bmp<220 spaces>.bat Content-transfer-encoding: base64 Content-disposition: attachment; filename="Colour Digital Camera VP.bmp<220 spaces>.bat"
Properly constructed attachments were correctly rejected.
Note: This problem only affected the Attachment Rejection mechanism, the attachments in question were still correctly scanned by GMS Anti-Virus and any viruses correctly detected.
Keywords:Juce Reject Attachments mime Spam checker GMS Anti-spam anti spam antispam