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Securing your webserver against common attacks

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  • phenomlabundefined

    1622031373927-headers-min.webp

    It surprises me (well, actually, dismays me in most cases) that new websites appear online all the time who have clearly spent an inordinate amount of time on cosmetics / appearance, and decent hosting, yet failed to address the elephant in the room when it comes to actually securing the site itself. Almost all the time, when I perform a quick security audit using something simple like the below

    https://securityheaders.io

    I often see something like this

    Not a pretty sight. Not only does this expose your site to unprecedented risk, but also looks bad when others decide to perform a simple (and very public) check. Worse still is the sheer number of so called “security experts” who claim to solve all of your security issues with their “silver bullet” solution (sarcasm intended), yet have neglected to get their own house in order. So that can you do to resolve this issue ? It’s actually much easier than it seems. Dependant on the web server you are running, you can include these headers.

    Apache

    <IfModule mod_headers.c>
Header set X-Frame-Options "SAMEORIGIN"
header set X-XSS-Protection "1; mode=block"
Header set X-Download-Options "noopen"
Header set X-Content-Type-Options "nosniff"
Header set Content-Security-Policy "upgrade-insecure-requests"
Header set Referrer-Policy 'no-referrer' add
Header set Feature-Policy "geolocation 'self' https://yourdomain.com"
Header set Permissions-Policy "geolocation=(),midi=(),sync-xhr=(),microphone=(),camera=(),magnetometer=(),gyroscope=(),fullscreen=(self),payment=()"
Header set X-Powered-By "Whatever text you want to appear here"
Header set Access-Control-Allow-Origin "https://yourdomain.com"
Header set X-Permitted-Cross-Domain-Policies "none"
Header set Strict-Transport-Security "max-age=63072000; includeSubDomains; preload"
</IfModule>

    NGINX

    add_header X-Frame-Options "SAMEORIGIN" always;
add_header X-XSS-Protection "1; mode=block";
add_header X-Download-Options "noopen" always;
add_header X-Content-Type-Options "nosniff" always;
add_header Content-Security-Policy "upgrade-insecure-requests" always;
add_header Referrer-Policy 'no-referrer' always;
add_header Feature-Policy "geolocation 'self' https://yourdomain.com" always;
add_header Permissions-Policy "geolocation=(),midi=(),sync-xhr=(),microphone=(),camera=(),magnetometer=(),gyroscope=(),fullscreen=(self),payment=();";
add_header X-Powered-By "Whatever text you want to appear here" always;
add_header Access-Control-Allow-Origin "https://yourdomain.com" always;
add_header X-Permitted-Cross-Domain-Policies "none" always;
add_header Strict-Transport-Security "max-age=63072000; includeSubdomains;" always;

    Note, that https://yourdomain.com should be changed to reflect your actual domain. This is just a placeholder to demonstrate how the headers need to be structured.

    Restart Apache or NGINX, and then perform the test again.


    That’s better !

    More detail around these headers can be found here

    https://webdock.io/en/docs/how-guides/security-guides/how-to-configure-security-headers-in-nginx-and-apache

    Author of OGProxy, Swatch, Threaded, Card, and most of Sudonix's bugs…

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  • phenomlabundefined

    ION brings clients back online after ransomware attack

    Blog
    12
    +0
    9 Votes
    12 Posts
    324 Views
    phenomlabundefined

    @crazycells said in ION brings clients back online after ransomware attack:

    you know, they believe the world revolves around them

    Haha, yes. And they invented [censored].

  • DownPWundefined

    Installing and Configuring CrowdSec in Cloudflare

    Security
    4
    +0
    3 Votes
    4 Posts
    285 Views
    phenomlabundefined

    @DownPW yeah, I seem to spend a large amount of my time trying to educate people that there’s no silver bullet when it comes to security.

  • Mike Jonesundefined

    Securing javascript -> PHP mysql calls on Website

    Solved Security
    2
    1 Votes
    2 Posts
    265 Views
    phenomlabundefined

    @mike-jones Hi Mike,

    There are multiple answers to this, so I’m going to provide some of the most important ones here

    JS is a client side library, so you shouldn’t rely on it solely for validation. Any values collected by JS will need to be passed back to the PHP backend for processing, and will need to be fully sanitised first to ensure that your database is not exposed to SQL injection. In order to pass back those values into PHP, you’ll need to use something like

    <script> var myvalue = $('#id').val(); $(document).ready(function() { $.ajax({ type: "POST", url: "https://myserver/myfile.php?id=" + myvalue, success: function() { $("#targetdiv").load('myfile.php?id=myvalue #targetdiv', function() {}); }, //error: ajaxError }); return false; }); </script>

    Then collect that with PHP via a POST / GET request such as

    <?php $myvalue= $_GET['id']; echo "The value is " . $myvalue; ?>

    Of course, the above is a basic example, but is fully functional. Here, the risk level is low in the sense that you are not attempting to manipulate data, but simply request it. However, this in itself would still be vulnerable to SQL injection attack if the request is not sent as OOP (Object Orientated Programming). Here’s an example of how to get the data safely

    <?php function getid($theid) { global $db; $stmt = $db->prepare("SELECT *FROM data where id = ?"); $stmt->execute([$theid]); while ($result= $stmt->fetch(PDO::FETCH_ASSOC)){ $name = $result['name']; $address = $result['address']; $zip = $result['zip']; } return array( 'name' => $name, 'address' => $address, 'zip' => $zip ); } ?>

    Essentially, using the OOP method, we send placeholders rather than actual values. The job of the function is to check the request and automatically sanitise it to ensure we only return what is being asked for, and nothing else. This prevents typical injections such as “AND 1=1” which of course would land up returning everything which isn’t what you want at all for security reasons.

    When calling the function, you’d simply use

    <?php echo getid($myvalue); ?>

    @mike-jones said in Securing javascript -> PHP mysql calls on Website:

    i am pretty sure the user could just use the path to the php file and just type a web address into the search bar

    This is correct, although with no parameters, no data would be returned. You can actually prevent the PHP script from being called directly using something like

    <?php if(!defined('MyConst')) { die('Direct access not permitted'); } ?>

    then on the pages that you need to include it

    <?php define('MyConst', TRUE); ?>

    Obviously, access requests coming directly are not going via your chosen route, therefore, the connection will die because MyConst does not equal TRUE

    @mike-jones said in Securing javascript -> PHP mysql calls on Website:

    Would it be enough to just check if the number are a number 1-100 and if the drop down is one of the 5 specific words and then just not run the rest of the code if it doesn’t fit one of those perameters?

    In my view, no, as this will expose the PHP file to SQL injection attack without any server side checking.

    Hope this is of some use to start with. Happy to elaborate if you’d like.

  • phenomlabundefined

    Hacked because you didn't listen ?

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    1 Posts
    202 Views
    No one has replied
  • phenomlabundefined

    Addressing vulnerability management

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    1 Posts
    203 Views
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  • phenomlabundefined

    Never underestimate the importance of security

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    1 Posts
    188 Views
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  • phenomlabundefined

    Why you should never neglect physical security

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  • phenomlabundefined

    Changing Passwords Regularly Actually Weakens Security

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