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 Security issues with this script
Author: C Morris 
Date:   17-01-03 19:42

It seems to me there are 2 issues with this script:

1) The size of the uploaded file is checked _after_ the upload has been done. If it is too large it is removed. However, by this time the file has already been written to disk. The ramifications here are significant.

For example:

MAXIMUM_UPLOAD = 100M
WWW partition size = 500M

User uploads a 5GB file. Since the file size is checked _after_ the upload the available disk space on the www partition has been filled. Potential server crash.

2) No maximum specified on number of files that can be uploaded.
Similar to the previous issue.

For example:

MAXIMUM_UPLOAD = 100M
www partition size = 500M

User Upload 10 x 100M files. Same result as issue 1.

These issues are not insurmountable but they should be taken into consideration by anyone who plans to post this script to their www server. Beware of blindly adding 3rd party scripts to your http server.

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 Re: Security issues with this script
Author: Russ 
Date:   21-06-10 07:45

I haven't tested it, but I think this would correct that and still display the correct message.
I will test this and update.

At line 279:

while ($Bytes = read($File_Handle,$Buffer,1024)) {
$BytesRead += $Bytes;
print OUTFILE $Buffer;
if ($BytesRead > $MAXIMUM_UPLOAD && $MAXIMUM_UPLOAD > 0) {
last;
}
}

That didn't work, oops...
Hopefully I'll be back.



Post Edited (22-06-10 10:32)

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