Hey there,
Have you heard about clickjacking attacks in the news recently? Sites like Twitter, Facebook and even Google have fallen victim to these deceptive attacks.
As an experienced cybersecurity professional, I can tell you that clickjacking is a serious threat all web apps need to guard against. And if you‘re running an Apache web server, you may be especially vulnerable.
Not to worry though! In this comprehensive guide, I‘m going to walk you through exactly how to lock down Apache against clickjacking attempts. By implementing the X-Frame-Options security header, you can effectively prevent other sites from framing or isolating parts of your web content.
Here‘s what we‘ll cover:
- What is clickjacking and how do these attacks work?
- Real-world examples of clickjacking incidents
- Why clickjacking poses a substantial risk for Apache sites
- An in-depth look at the X-Frame-Options response header
- Step-by-step instructions for enabling X-FO in Apache
- Additional clickjacking defenses to layer on top
And plenty more! By the end, your Apache server will be armed and ready to block clickjacking attacks.
So if you manage, administer or even just own an Apache site, you won‘t want to miss this. Let‘s get right into it!
What is Clickjacking and How Do Attackers Exploit It?
Clickjacking refers to an attack that tricks users into clicking on hidden elements on a web page. It‘s also sometimes called a UI redress attack or user interface redress attack.
The basic goal is to get an unknowing victim to interact with a page that appears harmless, but actually causes them to click on or trigger something malicious in the background.
Here‘s a quick real-world clickjacking example so you can see how this plays out…
A Recent Clickjacking Attack on Twitter
In early 2022, threat actors exploited the clickjacking vulnerability in Twitter to launch actual crypto scam ads.
The ploy was ingeniously simple. The attackers created web pages advertising fake crypto giveaways – "send 1 ETH to this wallet and we‘ll send 10 ETH back!" You know the kind.
Obviously that‘s a scam. But here‘s the tricky part…
These fake giveaway ads were then framed and layered overtop of actual Twitter content thanks to clickjacking. So users who went to tweet a message or check notifications didn‘t even realize they had been redirected to a scam site!
All they saw was familiar Twitter stuff under their mouse cursor. But when they went to click anything – Boom! – they actually clicked on the hidden crypto scam overlay instead.
Researchers estimate over 300k visitors were compromised by this recent Twitter clickjacking attack before it was shut down. But it shows just how easily this vulnerability can be exploited for fraud and theft.
And that‘s just one example. Clickjacking techniques have previously targeted sites like Facebook, PayPal, Google and many more. Any web app is at risk.
How Clickjacking Technically Works: Framing and Sandboxing
Now on a technical level, how do clickjackers manage to "hide" scam pages and malicious buttons overtop of normal content?
There‘s two main techniques:
Iframing
This uses iframe HTML elements to load a victim site inside a narrow, hidden frame. Attackers then put their own malicious scripts and interface elements overtop.
So unsuspecting visitors see the legitimate iframe content underneath, but anything they click triggers the invisible overlay instead.
Sandboxing
Similar idea here except no iframes. JavaScript code is used to "sandbox" parts of the victim page to only certain areas of the browser.
Attackers then overlay other malicious content on top. So users again just see the normal site layout, not realizing the whole interface has been compromised.
In both cases, the key thing that enables clickjacking attacks is the ability for one site to be loaded and displayed inside another.
The Fallout: Brand Damage, Fraud and More
Being clickjacked is bad news for both site owners and visitors. Some potential consequences include:
- Financial fraud – attackers driving payments or stealing credentials
- Account compromise – hijacked user accounts
- Malware or spyware installation
- Brand reputation damage if visitors think your site is unsafe
- Legal liability in some cases if negligence is proven
Plus clickjacking attacks can be notoriously hard to detect since they rely on deceiving users visually. Often the victim site doesn‘t even realize the attack is happening!
So what can site owners do? Just shrug and accept clickjacking as an inherent risk you can‘t control?
Thankfully no – there are safeguards you can put in place…which brings us to the X-Frame-Options header.
Guarding Apache Sites Against Clickjacking with X-Frame Options
If you run an Apache web server, one hugely effective clickjacking defense is to implement the X-Frame-Options HTTP header. This simple tweak allows you to control how other sites are permitted to frame or display your content.
The X-Frame-Options header has been around for awhile, but many site owners still don‘t utilize it. Let‘s change that today!
We‘ll cover:
- What X-Frame-Options does
- Available settings like SAMEORIGIN or DENY
- How to enable it in Apache configs
- Plus extras like troubleshooting tips
By the end, you‘ll have X-FO configured for max clickjacking protection.
An Intro to the X-Frame-Options Security Header
X-Frame-Options was designed to give site owners more control over iframe embedding and framing. Typically this is restricted for security reasons. You don‘t want random sites arbitrarily showing your content in hidden frames!
So browsers respect the X-Frame-Options header as a way for sites to declare their framing policy.
For example, Twitter has this header set:
X-Frame-Options: SAMEORIGINThis means only web pages originating from the same Twitter domain can frame Twitter content. All other cross-site framing is disallowed.
And with X-Frame-Options protecting your Apache site too, you can similarly lock things down.
Available X-Frame-Options Settings
There‘s a couple different values you can use with the X-Frame-Options header:
SAMEORIGIN
This is the most common and secure setting. As seen with Twitter above, it permits framing ONLY by pages from your own origin. Cross-domain framing is banned.
DENY
Does what it says – denies framing completely by all external sites. Most restrictive option but not always practical.
ALLOW-FROM uri
Whitelist framing only from a specific site by passing its URI . Other sites still forbidden.
So in summary:
- SAMEORIGIN = Framing allowed only from same site
- DENY = No framing allowed period
- ALLOW-FROM = Only allows framing from specified external site
Typically SAMEORIGIN offers the best security without being too restrictive. But you can tweak this setting to suit your site‘s needs.
Enabling X-FO in Apache to Block Clickjacking
Alright, let‘s get into the specifics of enabling X-Frame-Options on Apache!
Assuming you have admin level access, it just takes a quick config update. We‘ll walk through it.
Step 1 – Login and Backup Current Config
Access your Apache server and make sure you have permissions to modify the main configuration file. This is usually called httpd.conf or apache.conf.
Before editing, backup your current config file just to be safe!
Step 2 – Add the X-Frame-Options Header
Open httpd.conf in text editor, and add the following line near the top of the file:
Header always set X-Frame-Options "SAMEORIGIN"We‘re applying the Header directive to ALWAYS set X-Frame-Options for every site response, with the SAMEORIGIN policy value.
If you want to tweak the policy, you can substitute DENY or ALLOW-FROM domains. But SAMEORIGIN is recommended for Apache.
Step 3 – Save and Restart Apache
Save your httpd.conf changes and gracefully restart the Apache service.
If all went well, X-Frame-Options should now be enabled site-wide protecting all domains on this Apache instance!
If your Apache server is hosted with a web hosting provider, you may not have httpd.conf access. No worries!
On shared hosting you can use .htaccess files instead. Simply add this line:
Header always append X-Frame-Options SAMEORIGINSave this .htaccess to your site‘s root folder. The change will apply instantly without needing a web server restart.
Just make sure your hosting account does permit .htaccess tweaks. If not, you‘ll need to request X-FO be enabled at the server level by support staff.
Validating Everything is Working Correctly
To validate X-Frame-Options is active and blocking clickjacking properly, there‘s a couple checks we can do.
First, use your browser DevTools to inspect the HTTP headers being returned from Apache. You should see X-FO appearing on all responses now:
Secondly, use an online scanner tool to verify clickjacking protection works as expected:
https://www.marketingscoop.com/tools/x-frame-options-test
This checker simulates cross-domain framing requests to analyze if your X-FO policy blocks them appropriately.
If you see any issues with certain pages still allowing framing from unauthorized origins, first double check the X-FO syntax in your httpd.conf or .htaccess. Clear any caching or CDNs as well which could be serving stale pre-X-FO page versions.
But assuming Apache was configured right, everything should now be securely blocking external clickjacking attempts!
Extra Defenses – CSP, Frame Ancestors and More
While X-Frame-Options should lock things down nicely, I always recommend layered security for optimal protection.
Here‘s a couple other anti-clickjacking tools to consider alongside X-FO…
Content Security Policy Frame Ancestors
The Content-Security-Policy header contains a wide array of security directives for things like script loading, form submission rules, UI isolation scopes and more.
One directive called frame-ancestors aligns closely with X-Frame-Options, controlling permissible iframe parent domains.
Used together, CSP frame-ancestors double down on the clickjacking protections already provided by X-FO. So they nicely complement each other as layered defenses.
Other Clickjacking Mitigations
Beyond headers, there‘s a few other standard practices all sites should follow to deter clickjacking:
- Send X-Content-Type-Options: nosniff header to prevent MIME confusion attacks
- Include anti-framing code in page templates like JavaScript frame busters
- Educate users to watch for the padlock icon and valid HTTPS certificate on all sites to detect tampering
- Perform frequent penetration testing and vulnerability scans to identify any clickjacking risks
So while X-Frame-Options does the heavy lifting, combining other techniques gives attackers zero room to get in.
Wrapping Up
Phew – we covered a lot of ground here today!
You now understand exactly how sinister clickjacking attacks work and the unique risks they create for Apache-based sites.
Thankfully fending off clickjackers is straightforward with the simple yet powerful X-Frame-Options header now configured.
Between X-FO securely locking down framing policies, plus other layered defenses like CSP policies and frame busters, your Apache sites will be virtually clickjacking-proof.
But don‘t let your guard down! Make sure to periodically scan for any new web vulnerabilities, plus stay on top of cybersecurity news for the latest threats and protections.
I hope this guide gave you a helpful Apache security boost! Never hesitate to reach out if any other website or server issues pop up. Stay safe out there my friend!
