Canonical Hijacking in SEO: What It Is and How to Fix It If It Happens to You

by Salam Experts July 30, 2025 in Technical SEO

Reading Time: 2 minutes

What Is Canonical Hijacking?

Canonical hijacking is when Google mistakenly chooses another website’s URL as the canonical version of your page. This can result in:

Your site disappearing from search results
Your keywords ranking under someone else’s domain
Loss of traffic and revenue

Real Example: What Happened to NCATI.org

Recently, one of our clients at Salam Experts experienced this exact issue. Their domain https://ncati.org was ranking well until Google suddenly chose https://www.500centreisland.com (a completely unrelated site) as the canonical version.

All keyword rankings vanished, and Google started indexing the wrong website instead.

Common Causes of Canonical Hijacking

Copied content on another domain (scraping)
Framing your site via iframe or reverse proxy
Canonical tags pointing to the wrong domain
Improper HTTP headers (server misconfigurations)

How to Fix Canonical Hijacking: Step-by-Step

1. Check Canonical Tags on All Pages

Ensure every page has a self-referencing canonical tag like:

<link rel="canonical" href="https://yourdomain.com/page-url" />

Never point canonical tags to another domain unless it’s a proper redirect.

2. Inspect HTTP Headers

Use a tool like httpstatus.io or run:

curl -I https://yourdomain.com

Look for any suspicious headers like:

Link: <https://maliciousdomain.com/>; rel="canonical"

3. Use Google Search Console

Go to the URL Inspection Tool, paste the affected page, and check:

User-declared canonical – your version
Google-selected canonical – should also be yours

4. Block the Hijacking Site

If your site is being embedded via iframe or proxy, add this to your .htaccess file or server config:

Header always set X-Frame-Options "SAMEORIGIN"

To block a known hijacking referrer:

RewriteEngine on
RewriteCond %{HTTP_REFERER} 500centreisland\.com [NC]
RewriteRule .* - [F]

5. Report to Google

If Google keeps indexing the wrong site:

Use the Feedback option in Search Console
Provide full URL examples and a detailed explanation
Consider a DMCA takedown if your content was scraped

How to Prevent Canonical Hijacking in the Future

Set self-referencing canonical tags sitewide
Enable X-Frame-Options and/or Content Security Policy headers
Use Copyscape or Ahrefs to monitor content theft
Regularly audit your site with technical SEO tools

Need Help Fixing Canonical Hijacking?

At Salam Experts, we specialize in identifying and fixing technical SEO issues like this. If your site suddenly lost visibility or Google is indexing the wrong domain, we can help.

📩 Contact us today for a free SEO diagnostic check.

Author

Salam Experts

We are a digital marketing agency with over 17 years of experience and a proven track record of helping businesses succeed. Our expertise spans businesses of all sizes, enabling them to grow their online presence and connect with new customers effectively. In addition to offering services like consulting, SEO, social media marketing, web design, and web development, we pride ourselves on conducting thorough research on top companies and various industries. We compile this research into actionable insights and share it with our readers, providing valuable information in one convenient place rather than requiring them to visit multiple websites. As a team of passionate and experienced digital marketers, we are committed to helping businesses thrive and empowering our readers with knowledge and strategies for success.
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