All PHP files getting hacked

Question

Hey All,

Like always, just want to say thank you for all of the help and input in advance.

I have a particular site that I am the web developer for and am running into a unique problem. It seems that somehow something is getting into every single PHP file on my site and adding some malware code. I have deleted the code from every page multiple times and changed FTP and DB passwords, but to no avail.

The code that is added looks like this - eval(base64_decode(string)) - which the string is 3024 characters.

Not sure if anyone else has ran into this problem or if any one has ideas on how I can secure my php code up.

Thanks again.

Answer 1

You should move to another server. It would appear that the attacker has access to the server or is running some code as a background process which is overwriting the files. It may be possible to identify and remove the problem, but smart attackers will hide additional scripts etc to trip you up later.

Answer 2

yes i have ran into this problem myself, i take it you are on a shared host? are you perchance on rackspacecloud?

this is where i had that problem, the first thing you need to do right away is notify your host, this is a hosting issue, and i suspect the malware has gained access to your server on an ftp level.

make sure you have nothing chmod 777 world writable, if it needs to be writable by your app make it 775

hope this helps, good luck

Answer 3

You should change the file permissions so that only you can write to those files. 0777 (the default on some hosts, I believe) is just asking for trouble. See File Permissions.

Also, it's advisable to not put any files that aren't supposed to be accessible by URL outside of the public_html folder, for example, config files.

Answer 4

I had a similar problem. However, my problem was that I was running a python code evaluator on my site. As far as I remember you need to use eval() function to execute the python code. In one of my php files I had a weird eval statement. What kind of script are you developing? I mean does it involve evaluation of some other code?

Answer 5

The server itself could be compromised. Report the problem to your web host. What is their response?

An insecure PHP script coupled with incorrect file permissions could give the attacker the ability to modify your PHP files. To eliminate this possibility I would take the site down, delete all the files, re-upload, then switch permissions on the entire site to deny any writes to the file system.

Edit: As a short-term fix try asking your web host to disable eval() for your account. If they're worth their salt they should be running Suhosin which has an option to disable eval.

Answer 6

I've come across viruses that read filezilla conf files. I SWEAR TO GOD. at first i was: WOW, then i was: mother f*** sneaky b*stards.

Check your pc for viruses.

Answer 7

One of the possible scenarios is that somebody managed to get write access somehow and changing passwords etc. helped, but he left a php file that can still run.

See if there are any unknown files there. Or delete every damn thing and restore some backups.

Answer 8

You should use "disable_functions=eval,exec" in your php.ini or .htaccess as first measure.

Answer 9

Get the last modified time of your files, then go over to your access logs (FTP, HTTP whatever's open, if you don't know where they are ask your host) and find out who was mucking around on your system at that time.

Likely the attacker has installed a script that they can call periodically to re-infect any files you fix.

Answer 10

You should also note that (assuming you are using a hosting solution to host your site) that it's almost never your fault. An example being that networksolutions hosting company recently had a server hacked and over 1K webpages were affected, not due to security holes on each particular site, but due to some bad configuration/monitering of what was put on that particular server that hosts those sites. If you can't see any thing security wise wrong with your code, aka you sanitize everything properly and or you are running a non vulnerable version of whatever CMS you are using (if your using a CMS) then it's probably not an issue with your site, just the server in general.