Fixing DNS Hijacks: Bitdefender DNS Changer Detector Explained

How to Use Bitdefender DNS Changer Detector to Protect Your NetworkDNS (Domain Name System) controls how domain names are translated into IP addresses. A DNS changer (or DNS hijacker) redirects your device’s DNS settings to malicious servers that can steer you to phishing sites, inject ads, or monitor and tamper with your traffic. Bitdefender DNS Changer Detector is a free tool from Bitdefender that scans devices for unauthorized DNS changes and helps you restore safe settings. This article explains what the tool does, why you need it, how to use it step by step on different platforms, how to respond to findings, and best practices to protect your network going forward.

What is Bitdefender DNS Changer Detector?

Bitdefender DNS Changer Detector is a lightweight utility that inspects a device’s DNS configuration and detects whether DNS settings have been altered by malware, potentially exposing users to man-in-the-middle attacks, phishing and tracking. It supports Windows and Android and offers a simple interface for non-technical users while providing clear remediation steps when it finds suspicious settings.

Why DNS hijacking is dangerous

• DNS hijacking can redirect users to fake banking, email, or shopping sites that look legitimate but steal credentials.
• Malicious DNS servers can inject unwanted ads or tracking scripts into every web page.
• Hijacked DNS can be used to intercept two-factor authentication or other sensitive exchanges.
• Devices with changed DNS may be part of broader compromise, giving attackers persistent access.

Because DNS rules are applied at the system level, a hijack affects all browsers and apps that rely on standard name resolution—making detection and remediation a high priority.

Before you start: prerequisites and precautions

• Make sure the device is connected to the internet.
• On Windows, close other network utilities that might lock adapter settings.
• On Android, close any VPN apps and note that devices with root access might behave differently.
• If you manage a business network, plan to run scans during a maintenance window if you expect to change DHCP or router settings.

Create a quick note of your current network settings (IP and DNS servers) before making changes so you can revert if necessary.

How to download and install Bitdefender DNS Changer Detector

1. Visit Bitdefender’s official site or trusted download page for the DNS Changer Detector.
2. Choose the version for your platform (Windows or Android).
3. On Windows: run the installer and follow prompts. The tool is typically small and installs quickly.
4. On Android: install the APK from the official source or use Google Play if available. Grant only the permissions the app requests related to network diagnostics.

Always download security tools from official vendor pages to avoid counterfeit or tampered installers.

Step-by-step: scanning with Bitdefender DNS Changer Detector (Windows)

1. Launch the Bitdefender DNS Changer Detector app as Administrator (right-click → Run as administrator) to ensure it can inspect system-level settings.
2. On the main screen, click “Scan” (or the equivalent button). The tool will analyze the DNS settings of active network adapters and compare them against known safe values or expected configurations.
3. Review results:
   • If the tool reports no issues, your DNS settings match expected values.
   • If the tool reports DNS changed or suspicious DNS, it will display the current DNS addresses and often suggest remediation steps.
4. Follow remediation recommendations. On Windows this usually involves:
   • Resetting the adapter’s DNS settings to automatic (obtain DNS server address automatically), or
   • Manually setting DNS to a trustworthy resolver (for example, your ISP’s DNS, Cloudflare 1.1.1.1, Google 8.8.8.8, or another managed enterprise DNS).
5. After changes, re-run the scan to verify the DNS is corrected.
6. Reboot the machine to ensure settings persist and check other devices on the same network for similar issues.

Step-by-step: scanning with Bitdefender DNS Changer Detector (Android)

1. Open the app and grant any requested permissions for network diagnosis.
2. Tap “Scan” to let the app check your device’s DNS settings.
3. Interpretation:
   • Clean — system DNS is normal.
   • Modified — the app will list the DNS servers in use and explain why that might be dangerous.
4. Remediation options on Android may include:
   • Reverting DNS to default (system/ISP) settings.
   • Removing suspicious apps (the detector may point to apps that changed DNS).
   • Disabling or reconfiguring VPNs that change DNS.
5. After fixing, run the scan again and reboot the device.

If the detector finds malicious DNS settings

1. Note the DNS server addresses shown and check your router’s DNS settings next—DNS hijacks often occur at the router level.
2. Remove any suspicious apps or recently installed software on the affected device.
3. Change router admin credentials immediately if they are default or weak.
4. Update router firmware and device operating systems.
5. Reset router to factory defaults if you find unauthorized DNS entries there and reconfigure with secure credentials.
6. Consider performing a full antivirus scan on affected devices and changing important passwords (banking/email) from a known-clean device.
7. If you manage many devices or suspect a targeted attack, isolate the affected device(s) from the network while investigating.

Protecting your network long-term

• Keep operating systems, apps, and router firmware up to date.
• Use strong unique passwords for router admin and Wi‑Fi.
• Disable remote admin on consumer routers unless needed and secure it if enabled.
• Use reputable DNS providers and consider DNS over HTTPS (DoH) or DNS over TLS (DoT) where supported for encryption of DNS lookups.
• Use an endpoint protection product across devices to block malware that attempts DNS changes.
• Regularly run DNS checks (automate scans where possible) and audit network settings.

When to seek professional help

• Multiple devices show DNS changes simultaneously.
• You find persistent or reappearing malicious DNS entries after remediation.
• Sensitive or business-critical systems are affected.
• You suspect attacker lateral movement beyond DNS manipulation.

A professional incident response team can deep-scan your network, logs, and devices to ensure no other backdoors or persistence mechanisms exist.

Conclusion

Bitdefender DNS Changer Detector is a focused, user-friendly tool to find unauthorized DNS modifications that can expose users to phishing, tracking, and interception. Use it to scan devices regularly, follow the remediation steps when issues are found, check routers and other network infrastructure, and adopt preventive measures—firm passwords, firmware updates, encrypted DNS—to keep your network safer.