The Japanese Keyword Hack is a type of website compromise where hackers inject Japanese-language pages into your site, usually promoting fake stores. These pages get indexed by Google, which can damage your SEO reputation, reduce user trust, and potentially trigger search engine penalties.
In this article, you’ll learn:
- What the Japanese Keyword Hack is and how it works
- How to check if your site is affected
- How to remove the infection
- How to protect your website from future attacks
What is the Japanese Keyword Hack?
Hackers exploit vulnerabilities (outdated CMS, plugins, weak passwords) to gain access to your website and inject malicious code that:
- Creates fake pages filled with Japanese text and SEO metadata
- Modifies your site’s search appearance in Google (titles and descriptions)
- Uses cloaking to show different content to Googlebot vs. real users
- Often creates hidden admin accounts in your CMS
These fake pages often promote counterfeit products — sneakers, luxury goods, etc.
How to tell if your site is infected
Here are signs your site may be compromised:
1. Japanese text in Google Search
Search for site:yourdomain.com — If you see pages with Japanese characters you didn’t create, it’s a red flag.
2. Google Search Console warnings
Google may notify you about “Hacked content” or “Spammy structured data”.
3. Suspicious files on the server
Look for unfamiliar PHP files like wp-config-sample.php, wp-options.php, 404.php in unexpected locations.
4. Unknown admin accounts
Check your CMS (such as WordPress) for newly created users with administrative privileges.
Steps to fix the Japanese Keyword Hack
1. Backup website
Before making any changes, back up all your files and the database.
2. Clean malicious code
Scan files:
Use terminal commands like:
grep -r "base64_decode" .
grep -r "eval(" .
Look for obfuscated code in theme files, especially in functions.php, header.php, footer.php.
Restore clean files:
Compare with a fresh version of your CMS, theme, and plugins. Replace any compromised files.
3. Remove fake pages
- Delete all fake HTML/PHP pages created by attackers
- Check
.htaccessor routing configurations for malicious redirects
4. Check users and access
- Remove unknown administrator accounts
- Reset all user passwords
- Enable two-factor authentication (2FA)
5. Clean the database
Search for malicious content in your database — look for <script>, iframe, eval, or base64 in content or settings tables.
6. Request a Security review from Google
- Use Google Search Console to mark issues as resolved
- Request reindexing of affected pages
How to prevent future attacks
1. Keep everything updated
Outdated CMS, themes, and plugins are the #1 entry point for hackers.
2. Use strong passwords and 2FA
“Admin123” is not secure. Use complex passwords and enable two-factor authentication.
3. Set up a Web Application Firewall (WAF)
Utilize tools such as WebTotem, Sucuri, Wordfence, or Cloudflare to block malicious traffic.
4. Monitor your website for changes
Recommended tools:
5. Disable theme/plugin editors in WordPress
Add the following to wp-config.php:
define('DISALLOW_FILE_EDIT', true);
Conclusion
The Japanese Keyword Hack is more than just a visual issue — it’s a serious threat to your site’s reputation and security. Regular updates, access control, and monitoring are essential for maintaining your website’s protection.
If you don’t have experience cleaning malicious code, reach out to a professional — trying to fix it yourself may make things worse.
If you’re struggling to fix it on your own, consider contacting the WebTotem team — we will help you clean up your site and restore its reputation.
