Japanese Keyword Hack: What It Is & How to Protect Your Website
If your brand name suddenly appears in Google with strange Japanese text, pharma terms, or fake store pages, you’ve likely been hit by the Japanese Keyword Hack (also called Japanese SEO spam). It’s a common attack—especially on CMS sites like WordPress—that quietly injects thousands of spam pages, damages rankings, and erodes user trust.
This guide breaks down what’s happening, how to find and fix it, and the steps to harden your site so it doesn’t happen again.
TL;DR (Quick Summary)
- What it is: Malware creates cloaked, auto-generated Japanese pages on your site to rank for spam keywords.
- What you’ll notice: Odd Japanese results for site:yourdomain.com, a spike in index count, unfamiliar sitemaps/users, and weird redirects that only Googlebot sees.
- How to fix: Clean files & database, remove hacked pages (return 404/410; do not block with robots.txt), revoke unauthorized users (incl. Google Search Console), then request re-crawls.
- How to prevent: Patch everything, enforce 2FA, least-privilege access, WAF, secure backups, and continuous monitoring.
What Is the Japanese Keyword Hack?
The attacker injects code that auto-generates Japanese-language pages on your domain (often under random folders) and links them to spammy affiliate stores or phishing destinations. In many cases, the malware cloaks content so regular visitors don’t see it—but search engines do. The result: your brand starts ranking for unrelated Japanese queries and your legitimate content loses visibility.
How This Hack Works
1. Initial entry: Vulnerable plugins/themes, weak passwords, outdated CMS, or leaked credentials.
2. Payload & persistence: Malicious PHP/JS gets dropped into uploads/themes and scheduled via cron or autoloaded options; attackers may tweak .htaccess to treat Googlebot differently (classic cloaking).
3. Mass page generation: Thousands of Japanese pages and even fake sitemaps get created and submitted to search engines.
4. Search Console abuse: Some attackers add themselves as owners/users to Google Search Console to push or monitor spam indexing.
Red Flags: How to Tell If You’re Infected
- Google search test: site:yourdomain.com 日本 or site:yourdomain.com ジャパン shows pages you never created.
- Search Console spikes: Unusual surge in indexed pages; unknown sitemaps in Indexing → Sitemaps.
- Weird users: Unrecognized admins in your CMS, hosting panel, or Search Console → Users & permissions.
- Server anomalies: Suspicious .htaccess, wp-config.php edits, or base64/eval-heavy files in /wp-content/uploads/.
Business Impact (Why You Must Act Fast)
- SEO damage: Search engines associate your domain with spam; rankings and CTR drop.
- Brand trust: Users clicking “your” result land on scammy stores.
- Security risk: The same hole can be used for phishing or malware distribution.
Google’s guidance: clean the site, return 404/410 for spam URLs, and avoid blocking via robots.txt so the junk can be crawled and removed from the index.
Step-by-Step Removal Playbook (Works for WordPress & Most CMSs)
Before you begin: Take a full backup (files + database). If disaster strikes, you can roll back safely.
1. Lock Down Access (Immediate)
- Change all passwords: hosting, SFTP/SSH, database, CMS, CDN, and API keys.
- Enable 2FA for CMS/host and Search Console.
- In Search Console → Users & permissions, remove unknown users and review ownership verification methods.
2. Put a Temporary Shield
- If possible, enable a WAF (at host/CDN) to block known bad patterns while you clean.
3. Scan & Clean Files + Database
- Use reputable scanners or security plugins to identify infected files; then manually inspect hotspots:
- /wp-content/uploads/, /wp-includes/, active theme & child theme, mu-plugins
- .htaccess, wp-config.php, index.php
- Database tables like wp_options, wp_posts (strange admins, base64 blobs, spam posts)
- Replace core CMS files with fresh copies from the official source.
- Delete unknown sitemaps and spam directories.
4. Remove Spam From the Index (The Right Way)
- Return 404 (not found) or 410 (gone) for spam URLs. Do not redirect them to your homepage and do not block via robots.txt—Google needs to crawl the 404/410 to drop them.
- In Search Console → Removals, temporarily hide the worst offenders to reduce short-term brand risk while Google re-crawls.
5. Re-verify, Resubmit, Recrawl
- Resubmit a clean sitemap, and use URL Inspection → Request indexing for key pages.
- Watch Indexing → Pages and Security issues for fresh alerts.
6. Monitor Rankings & Recovery
- Recovery time varies (weeks to a few months) based on site size and contamination depth—keep logs and continue cleaning anything that resurfaces.
Hardening Guide: Prevent the Next Attack
- Patch everything: Core, themes, plugins—remove what you don’t use.
- Least privilege: Separate accounts; no shared super-admins; disable file editing in the CMS.
- 2FA everywhere: CMS, host, Search Console, Git, CDNs.
- Lock entry points: Limit /wp-admin, rate-limit or disable XML-RPC if not needed.
- WAF/CDN security: Turn on bot filtering, firewall rules, and automatic virtual patching.
- Backups you can trust: Daily off-site backups with versioning; test restores quarterly.
- File integrity & alerts: Enable change detection and auto-alerts for core/system files.
- Security headers & HTTPS: Enforce HSTS, X-Content-Type-Options, CSP where feasible.
India-Specific Tips
- WhatsApp & email alerts: Set up instant alerts for downtime/index spikes—teams in India often coordinate via WhatsApp; seconds matter during an incident.
- Hosting choice: Prefer providers with local PoPs, reliable WAF options, and quick support SLAs.
- Regulatory hygiene: Keep accurate contact details on your website and in domain WHOIS/ICANN records—helps with faster verifications during recovery.
Frequently Asked Questions
1. Will I lose all my Google rankings?
Not necessarily. If you clean thoroughly, return 404/410 for spam URLs, and fix the vulnerability, most sites gradually regain visibility.
2. Should I block spam URLs in robots.txt?
No. Blocking prevents Google from seeing the 404/410 and delays removal from the index.
3. How do I know it’s truly gone?
- No more new spam URLs in Search Console
- Clean server files and database for two+ weeks
- No suspicious users/sitemaps; WAF shows reduced attack noise
4. Is this only a WordPress problem?
WordPress is heavily targeted due to market share, but any CMS can be hit if it’s unpatched or misconfigured.
Handy Checklist (Save This)
- Rotate all passwords + enable 2FA
- Remove unknown Search Console and CMS users
- Scan & clean files/database; replace core
- Delete malicious sitemaps; return spam URLs 404/410
- Resubmit sitemap; request indexing for key pages
- Turn on WAF; set file-change alerts
- Schedule patching and verify off-site backups
Example Incident Timeline (What “Good” Looks Like)
- Day 0–1: Lock down access, snapshot backup, remove rogue users, start scanning
- Day 2–3: Clean files/DB, push WAF rules, remove spam URLs properly, resubmit sitemap
- Day 4–14: Monitor index, fix stragglers, request recrawls for crucial pages
- Weeks 3–8: Rankings stabilize; move to monthly security maintenance
Secure Your Website with Blow Horn Media
Don’t let a Japanese Keyword Hack ruin your brand’s online reputation or SEO rankings. Blow Horn Media specializes in performance-driven digital strategies and advanced website security solutions to keep your business safe and thriving.
Call us today or drop us an email to schedule a quick website audit and get expert guidance on cleaning, securing, and future-proofing your site.
Let’s build a safer, smarter, and more profitable digital presence — together!