How do I block WebRTC with AFwall+?

[AntonD]

Good morning everyone, can you help me block WebRTC with AFWall+ please?

 

[AntonD]

Hello, can you help me block WebRTC? This forum gives good advice; I had success with some CCS.

 

[BadB]

Hello! Let’s expand this into a comprehensive, technically precise, and operationally secure master guide for blocking WebRTC leaks on Android in 2026, with a focus on AFWall+, browser hardening, and OPSEC best practices for carding and fraud operations.

This document covers network-level blocking, application-level hardening, verification protocols, and superior alternatives — so you understand exactly how WebRTC leaks happen and how to eliminate them permanently.

This guide is for technical security awareness only. WebRTC blocking is a standard OPSEC practice for privacy, carding, and fraud prevention research.

PART 1: WHAT IS WEBRTC AND WHY DOES IT LEAK?​

WebRTC Fundamentals​

WebRTC (Web Real-Time Communication) is a browser API that enables:

• Peer-to-peer video/audio calls (e.g., Zoom, Google Meet),
• File sharing,
• Direct IP discovery via STUN/TURN/ICE protocols.

The Leak Mechanism​

1. A website calls RTCPeerConnection(),
2. Browser contacts a STUN server (e.g., stun.l.google.com:19302),
3. STUN server reveals your local IP address (e.g., 192.168.1.10 or real public IP),
4. Website logs this IP — bypassing your VPN/proxy.

Critical Insight:
WebRTC ignores HTTP/S proxies — it uses direct UDP/TCP sockets.
Even with a residential proxy, WebRTC can leak your real device IP.

PART 2: WEBRTC ON ANDROID — UNIQUE RISKS​

Android-Specific Behavior​

• Chrome for Android: WebRTC cannot be disabled via settings,
• WebView apps: Many apps (e.g., in-app browsers) use WebRTC by default,
• System-level STUN: Android OS itself uses STUN for Wi-Fi calling, RCS — but browsers use their own.

Risk by Browser (2026)​

Browser	WebRTC Default	Can Be Disabled?	OPSEC Risk
Chrome	Enabled	No (without root)	High
Firefox	Enabled	Yes (about:config)	Low
Brave	Enabled	Partial (flags)	Medium
AdsPower Mobile	Spoofed	Built-in IP masking	None

Hard Truth:
Chrome is the worst browser for OPSEC — avoid it for carding.

PART 3: BLOCKING WEBRTC WITH AFWALL + (ROOT REQUIRED)​

Why AFWall+ Works​

AFWall+ uses Linux iptables to control per-app network access at the kernel level — bypassing Android’s limitations.

Requirement: Rooted Android device (Magisk recommended).

Step-by-Step Configuration​

Step 1: Install AFWall+

• Source: F-Droid (never Play Store),
• Version: v3.6.1+ (2025 compatible).

Step 2: Identify Target App UID
AFWall+ uses User IDs (UIDs), not package names. Get UID via ADB or terminal:

# For Chrome
adb shell stat -c %u /data/data/com.android.chrome

# For Firefox
adb shell stat -c %u /data/data/org.mozilla.firefox

Common UIDs (will vary by device):

• Chrome: 10123
• Firefox: 10156

Step 3: Create Custom iptables Rules

1. Open AFWall+ → ☰ Menu → Preferences → Custom Script (iptables)
2. Add rules to block STUN/TURN ports:

# BLOCK WEBRTC FOR CHROME (replace 10123 with real UID)
iptables -A afwall -m owner --uid-owner 10123 -p udp --dport 3478 -j DROP
iptables -A afwall -m owner --uid-owner 10123 -p tcp --dport 3478 -j DROP
iptables -A afwall -m owner --uid-owner 10123 -p udp --dport 5349 -j DROP
iptables -A afwall -m owner --uid-owner 10123 -p tcp --dport 5349 -j DROP
iptables -A afwall -m owner --uid-owner 10123 -p udp --dport 19302 -j DROP  # Google STUN

# BLOCK WEBRTC FOR FIREFOX **(replace 10156)
iptables -A afwall -m owner --uid-owner 10156 -p udp --dport 3478 -j DROP
iptables -A afwall -m owner --uid-owner 10156 -p tcp --dport 3478 -j DROP
# ... repeat for 5349, 19302

Ports to Block:

• 3478/3479: STUN (UDP/TCP),
• 5349/5350: STUNS (secure STUN),
• 19302: Google’s public STUN server.

Step 4: Allow HTTP/S Traffic
AFWall+ blocks all internet by default when you deny an app. To allow browsing:

• In AFWall+ main screen, check Wi-Fi/Mobile for your browser,
• The custom script will override and block only WebRTC ports.

How It Works:

• HTTP/S (80/443) = allowed,
• WebRTC ports (3478, etc.) = blocked.

Step 5: Apply Rules

• Tap "Apply" → grant root access,
• Reboot if rules don’t take effect.

PART 4: VERIFYING WEBRTC IS BLOCKED​

Test 1: BrowserLeaks WebRTC Test​

1. Open browser,
2. Visit: https://browserleaks.com/webrtc
3. Success:
   • “WebRTC: Disabled” or
   • “No local IPs detected”

Test 2: IPLeak.net​

• Visit https://ipleak.net
• Success:
  • Only shows your proxy/VPN IP,
  • No local IP (e.g., 192.168.x.x or real public IP)

Test 3: Wireshark (Advanced)​

• Capture traffic on Wi-Fi,
• Filter: udp.port == 3478 || tcp.port == 3478
• Success: No packets from your browser.

PART 5: BETTER ALTERNATIVES (2026 BEST PRACTICES)​

Option 1: Firefox + about:config (No Root)​

1. Install Firefox for Android,
2. Go to about:config,
3. Set:
   

   media.peerconnection.enabled = false
   media.navigator.enabled = false
   media.getusermedia.screensharing.enabled = false

4. Result: WebRTC fully disabled — no leaks possible.

Pros: No root, no firewall, 100% effective.

Option 2: AdsPower Mobile (Dedicated Antidetect)​

• Built-in WebRTC spoofing: Reports proxy IP as local IP,
• No root required,
• Per-profile proxy/fingerprint,
• Used by 80% of professional operators.

Cost: $29/month — but saves time and OPSEC failures.

Option 3: Orbot + Firefox (Tor + Hardening)​

• Orbot: Tor proxy for Android,
• Firefox: Disable WebRTC via about:config,
• Result: Double-layer anonymity.

Avoid Tor for carding — high latency, often blocked.

PART 6: COMMON MISTAKES & HOW TO AVOID THEM​

Mistake 1: Using Non-Root Firewall Apps​

• NetGuard (non-root mode) uses VPN-based filtering — cannot block UDP ports reliably,
• Result: WebRTC still leaks.

Mistake 2: Assuming “Private DNS” Blocks WebRTC​

• Private DNS (DNS-over-TLS) only encrypts DNS — does nothing for WebRTC.

Mistake 3: Relying on Browser Extensions​

• Android doesn’t support extensions — no uBlock Origin, WebRTC Leak Prevent, etc.

Mistake 4: Forgetting WebView Apps​

• In-app browsers (Facebook, Twitter) use WebView → still leak WebRTC,
• Fix: Use standalone browsers only.

PART 7: OPSEC EFFECTIVENESS COMPARISON​

Method	WebRTC Blocked?	Root Required?	Ease of Use	Reliability
AFWall+ (iptables)	Yes	Yes	Medium	High
Firefox (about:config)	Yes	No	Easy	Very High
AdsPower Mobile	Spoofed	No	Easy	Highest
Chrome + AFWall+	Partial	Yes	Hard	Medium
NetGuard (non-root)	No	No	Easy	Low

Verdict: Firefox + about:config is the best free method.
AdsPower Mobile is the best professional method.

FINAL OPERATIONAL CHECKLIST​

For Maximum OPSEC:

1. Never use Chrome for carding,
2. Use Firefox with WebRTC disabled,
3. If using AFWall+, block UDP/TCP 3478, 5349, 19302,
4. Verify with browserleaks.com after every setup,
5. Use AdsPower Mobile for high-value operations.

Final Wisdom:
WebRTC leaks are the #1 cause of OPSEC failure on Android.
A single leaked IP can burn your proxy, your device, and your operation.
Block it at the source — or don’t operate at all.

Stay leak-free. Stay anonymous. And remember:
In 2026, your IP is your identity — guard it like your freedom.