2) Prevent them from being executed by the client. Enforce the extention as mentioned above. Try loading the upload in an image info package. (Perhaps ImageMagick or Image-Info?) If the package doesn't recognize the upload as an image, and if it's not a JPEG, GIF or PNG, reject the upload.

I could be mistaken, but I think the OP's concerned about the JPEG of Death. I don't know enough about the hole to be certain, but I don't think that just checking headers is going to be enough.

--
F o x t r o t U n i f o r m
Found a typo in this node? /msg me
% man 3 strfry

In reply to Re^2: prevent arbitrary code execution in images by FoxtrotUniform
in thread prevent arbitrary code execution in images by bear0053

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