Title: Possible Security Vunerability:  admin-bar.php
Last modified: August 21, 2016

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# Possible Security Vunerability: admin-bar.php

 *  Resolved [Another Guy](https://wordpress.org/support/users/another-guy/)
 * (@another-guy)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/)
 * I am noticing a pile of traffic all of a sudden on different wordpress installs,
   attempting to directly post to admin-bar.php. It looks like an attempt to add
   malware onto the admin bar, which would potentially permit either a user privilege
   escalation or to try to obtain credentials or similar.
 * Thankfully, I get errors like this:
 * PHP Fatal error: Call to undefined function add_action() in /var/www/website/
   wp-includes/admin-bar.php on line 48
 * Interestingly, I didn’t see these before installing 3.9.1, which means either
   the hack was on previous version, or they have found something new.
 * I did find one cached page on Google (not the actual page anymore) that showed
   this being used to install a rootkit. Again, not sure of the mechanics, but I
   am seeing plenty of activity on this.

Viewing 15 replies - 1 through 15 (of 22 total)

1 [2](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/page/2/?output_format=md)
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 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985290)
 * Just because hackers are targeting your sites’ admin bars does not mean that 
   the admin bar itself is the vector. Only that it’s a victim of the hack. You 
   need to start working your way through these resources:
    [http://codex.wordpress.org/FAQ_My_site_was_hacked](http://codex.wordpress.org/FAQ_My_site_was_hacked)
   [http://wordpress.org/support/topic/268083#post-1065779](http://wordpress.org/support/topic/268083#post-1065779)
   [http://smackdown.blogsblogsblogs.com/2008/06/24/how-to-completely-clean-your-hacked-wordpress-installation/](http://smackdown.blogsblogsblogs.com/2008/06/24/how-to-completely-clean-your-hacked-wordpress-installation/)
   [http://ottopress.com/2009/hacked-wordpress-backdoors/](http://ottopress.com/2009/hacked-wordpress-backdoors/)
 * Anything less will probably result in the hacker walking straight back into your
   site again.
 * Additional Resources:
    [Hardening WordPress](http://codex.wordpress.org/Hardening_WordPress)
   [http://sitecheck.sucuri.net/scanner/](http://sitecheck.sucuri.net/scanner/) 
   [http://www.unmaskparasites.com/](http://www.unmaskparasites.com/) [http://blog.sucuri.net/2012/03/wordpress-understanding-its-true-vulnerability.html](http://blog.sucuri.net/2012/03/wordpress-understanding-its-true-vulnerability.html)
 *  Thread Starter [Another Guy](https://wordpress.org/support/users/another-guy/)
 * (@another-guy)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985293)
 * Thank you, but my sites were NOT hacked – I am seeing people make direct calls
   to that function, which is highly unusual.
 * My sites are as secure as wordpress sites can be. So pointing me to a bunch of“
   your sites has been hacked” information isn’t helping.
 * I am reporting an issue, not asking for help. Is it hard to tell the difference?
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985294)
 * > I am noticing a pile of traffic all of a sudden on different wordpress installs,
   > attempting to directly post to admin-bar.php
   >  […] PHP Fatal error: Call to 
   > undefined function add_action() in /var/www/website/wp-includes/admin-bar.php
   > on line 48
 * Hmm… That sounds like a hacked site to me.
 *  Thread Starter [Another Guy](https://wordpress.org/support/users/another-guy/)
 * (@another-guy)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985298)
 * Nope. That is a direct call attempting to use that functions to do something.
   See, you can access that function without being logged in, which appears to be
   pretty silly.
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985299)
 * > That is a direct call attempting to use that functions to do something.
 * Then can we see the full error message?
 *  Thread Starter [Another Guy](https://wordpress.org/support/users/another-guy/)
 * (@another-guy)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985305)
 * That is all that ends up in the error log at this point, I don’t have full verbose
   logs on (it would be a machine killer to do that). But looking at it, it appears
   to be a direct call (as it isn’t attributed to another page), with no referring
   page.
 * Looking at the code, it appears to be trying to call a function that has not 
   been loaded, as they are directly calling the admin-bar.php file.
 *  [kyle_t](https://wordpress.org/support/users/kyle_t/)
 * (@kyle_t)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985440)
 * I have been noticing the same error coming through our logs. I am interested 
   in any more information that you find about this attempted exploit.
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985442)
 * > That is all that ends up in the error log at this point
 * Then how do you know that this is a direct call? It still smacks of a hacked 
   site.
 *  [kyle_t](https://wordpress.org/support/users/kyle_t/)
 * (@kyle_t)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985445)
 * I was able to recreate the error in the error logs with our ip by visiting /wp-
   includes/admin-bar.php directly, I did not try posting any data to it
    I have
   to agree with another guy that the site is not hacked, it is just an attempt 
   to exploit.
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985447)
 * So where is the issue?
 *  [kyle_t](https://wordpress.org/support/users/kyle_t/)
 * (@kyle_t)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985459)
 * I don’t see any issue, as of now. Obviously these files are not supposed to be
   accessed directly, and accessing admin-bar.php directly doesn’t do much since
   the add_action() function is not defined within that file. (It is defined in 
   wp-includes/plugin.php)
 * But I’m going way out on a limb here and saying maybe there is a plugin or some
   other malware that makes an edit to that file so that when that file is accessed
   directly it leads to a backdoor into wordpress admin. Again just speculation 
   and also worst case scenario.
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985461)
 * None of the plugins hosted at wordpress.org make edits to any core WordPress 
   files.
 *  Thread Starter [Another Guy](https://wordpress.org/support/users/another-guy/)
 * (@another-guy)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985466)
 * “I don’t see any issue”
 * In simple terms, if someone is knocking on a particular file on more than one
   installation, then you have to ask why. You make the assumption of an already
   hacked wordpress install, my feeling is this is much more an attempt to create
   a hole, not to profit from it.
 * I tend to go with Kyle T on this one, it looks like someone has figured out a
   potential hole, or that a different hack modifies this file to allow for a back
   door to create a recurring hack. It looks potentially like someone checking to
   see if an installation has been hacked or modified.
 * It’s also the first file in that directory, alphabetically.
 *  Moderator [Jan Dembowski](https://wordpress.org/support/users/jdembowski/)
 * (@jdembowski)
 * Forum Moderator and Brute Squad
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985467)
 * > In simple terms, if someone is knocking on a particular file on more than one
   > installation, then you have to ask why.
 * That parts easy: some installations get compromised, that file get’s hacked and
   BOOM! you’re done.
 * > You make the assumption of an already hacked wordpress install, my feeling 
   > is this is much more an attempt to create a hole, not to profit from it.
 * That’s just not the case.
 * > I tend to go with Kyle T on this one, it looks like someone has figured out
   > a potential hole, or that a different hack modifies this file to allow for 
   > a back door to create a recurring hack. It looks potentially like someone checking
   > to see if an installation has been hacked or modified.
 * There are a lot of insecure hosts and installations running insecure add-on code.
   The bad guys look for systems that have been compromised _already_. That is all
   that those probes mean.
 * Now if someone does know of a means to exploit the stock WordPress files then
   please report it. But this part:
 * > I am noticing a pile of traffic all of a sudden on different wordpress installs,
   > attempting to directly post to admin-bar.php
 * Doesn’t mean that file is exploitable. It means someone is looking for a copy
   that has already been hacked.
 *  Thread Starter [Another Guy](https://wordpress.org/support/users/another-guy/)
 * (@another-guy)
 * [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/#post-4985468)
 * I understand your points Jan, but I think you are missing context here.
 * Why this file, and not any others? It’s not generally a file people would access(
   unless they are logged in) but potentially code added here would be executed 
   by someone with admin level privileges. If they are just testing to see if wordpress
   exists, there are easier ways. Moreover, as emsi pointed out, these are not files
   that generally can be modified by a plug in, so it wouldn’t be some simple thing.
 * Moreover, I did find at least one cached example of this file turned into a rootkit
   install point. It basically Google caching the page, but there is no current 
   version. So it suggests someone has found a way either to exploit that file directly
   or to use it as the “exploited file” for some other hack. Either way, it’s worth
   noting.
 * I have to ask though: Why is there such a strong resistance to accepting a report
   of potential hacking activity?

Viewing 15 replies - 1 through 15 (of 22 total)

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The topic ‘Possible Security Vunerability: admin-bar.php’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 22 replies
 * 6 participants
 * Last reply from: [Nicki Faulk](https://wordpress.org/support/users/nitallica/)
 * Last activity: [11 years, 11 months ago](https://wordpress.org/support/topic/possible-security-vunerability-admin-barphp/page/2/#post-4985487)
 * Status: resolved

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