Why do we need proxies with UDP and what does the WebRTC leak in Antidetect have to do with it?

[chushpan]

How will any anti-fraud system detect IP address substitution even when working through a proxy + VPN (or just a proxy)? Why do we need proxies with UDP support? Why won't Antik (antidetect browser) help with WebRTC checking, even if all services show that everything is fine?

In this article, we will figure out how WebRTC can "give out" your real IP address, why regular proxies often do not solve this problem and how to deal with it.

Proof

What is WebRTC and how does Antifraud systems use it?​

WebRTC is a protocol for transmitting streaming data. It is most often used in JavaScript.

• Anti-fraud systems use WebRTC to detect various characteristics of your system. For example, WebRTC (especially in Chrome) may use the UDP protocol by default, which allows you to make a request directly from the user's real IP address.
• If you use a proxy without UDP support (and most proxies do), WebRTC requests will bypass the proxy and reveal your real IP. Even if all other connections go through the proxy, it is WebRTC traffic that can break through NAT and show your real IP.
• If you are connected via VPN without a proxy, WebRTC will give out the IP address of the VPN. But for anti-fraud systems, this is also a reason to "add" fraud-score points, since they see that you are using a VPN connection instead of a regular provider.
• There are few proxy services on the market that provide full UDP support. We hope that proxy service developers will also read this article and expand the functionality, but so far there are only a few such solutions.

How exactly does WebRTC "leak" your real IP?​

When we visit a website (for example, antifraud.com), the antifraud system loads special JavaScript scripts into the browser. Usually, these scripts are heavily encrypted (obfuscated), so it is extremely difficult to read them with the naked eye.

Detection steps:

1. The site makes a request to its internal server via TCP (a regular fetch request)
2. The anti-fraud system responds to this request and “tells” the browser: “Make another additional request to my STUN server on such-and-such port.” This initiates an additional check.
3. "The browser has no choice but to fulfill this request. And no anti-malware can prevent this, since it is impossible to catch and block all addresses.
4. The browser makes a UDP request - after all, the STUN server needs to be accessed via UDP.
5. Antifraud easily compares your “regular” TCP request (via proxy) and UDP request (directly) within the same session.

• If the IP addresses are different, then you are using a proxy or VPN.
• This way you can determine your real IP (or at least VPN IP).

Example: you can check the operation of this scheme through our test service -
http://172.86.65.208:8080

The algorithm is implemented there in the same way as described above.

What to do?​

First and foremost: The proxy must support UDP. If there is no

UDP support at the proxy level, then neither Antik, nor Router, nor Goodwin (¬‿¬) will be able to “screw” it on for you — it must be there initially. It is also important to understand that UDP support can only be in SOCKS5 (HTTP / HTTPS / SOCKS4 simply does not have it). In addition, not all SOCKS5 proxies work correctly with UDP. You can check SOCKS5 support for UDP using our software (ZloyRouter).

In our group, we also tested many proxy services for UDP support - but only a few actually provide it.

What about VPN?​

VPN (OVPN, PPTP, WireGuard) always supports UDP out of the box, so our test will show:

TCP IP = UDP IP, just like the average user.

This is because VPN and proxy work fundamentally differently and connect differently:

• VPN tunnels all your traffic,
• Proxy (including SOCKS5) works at the application level (in our case, the antidetect browser).

Read about levels here. Our test, as we have already found out, can use the transport layer (UDP), so VPN usually "passes" the test without problems, but the proxy - only if it supports UDP and is connected correctly.

Problems with Chrome when working via SOCKS5​

Even if your proxy correctly supports UDP, and you launch a browser with good SOCKS5, you still won’t be able to pass our test. The reason is that “our favorite” Chrome (and any antidetect browsers based on Chromium) does not support full-fledged operation of WebRTC traffic (UDP, STUN, etc.) through a SOCKS5 proxy.

Chrome and Chromium-based antidetect browsers do not allow WebRTC traffic (UDP, STUN, etc.) through SOCKS5. This is a long-standing "feature" (or limitation) related to the fact that WebRTC by default tries to directly "break through" NAT, bypassing any proxy. In Firefox, these requests are simply blocked.

Conclusion: all Chrome-based antidetect browsers (and most of them) are subject to this problem.

Write in the comments if you are interested in why this happens

How to get around this?​

ZloyRouter

You can overcome the problem by correctly "distributing" SOCKS5. We solve this with the ZloyRouter program. You just insert your SOCKS5 into it. If SOCKS5 really supports UDP, WebRTC traffic will go as it should - through a proxy, and the test will not suspect a trick.

[SOCKS5 (UDP support)] --> [ZloyRouter] --> [Chrome/Antidetect]

1. It's immediately obvious if you have a problem with UDP.
2. If there was a problem, you automatically solve it.

If I block UDP, will it be OK?​

This is certainly better than "leaking" your real IP address. If you encounter a similar WebRTC check somewhere in the "wild", there is a chance that you will pass it.

However, the vast majority of regular users do not have WebRTC blocked, and for them TCP IP = UDP IP. If you have WebRTC/UDP blocked, the anti-fraud system may suspect something is wrong and add additional "fraud points".

Why don't all the "antidetects" show the leak?​

You can check yourself on browserleaks.com/webrtc or similar services and not see real IP leaks. But these services are known to antidetect browsers and their developers:

• They simply replace the necessary data and say: “The problem does not exist.”
• This lulls the user's vigilance.
• In fact, the technique of “penetrating” IP via WebRTC-UDP has been known since 2019, and any anti-fraud system can (and will) use it.

The problem can be solved by correctly forwarding the proxy.

By the way, if our test site does not open in Chrome, it means that proxy providers simply blocked it to hide the fact that they do not support UDP. For example, Astraproxy and IPRoyal did this. They say "we have UDP", but for some reason the test site is unavailable. Draw your own conclusions.

Some antidetect browsers also block our test on purpose, and at the same time "everything is fine with them", but in fact the problem remains.

Summary​

Use good software, subscribe to the group (https://t.me/Zl0yTeam) and don't be discouraged. Good luck to everyone! You can overcome this - you just need to distribute your SOCKS5 correctly - We have solved this problem with our ZloyRouter program. You just insert your SOCKS5 into it and if it supports UDP, then the traffic will go as it should through the proxy and the test will not suspect anything. Firstly, you at least know right away whether you have this problem. Secondly, you automatically solve it if it does.

 

[hhttpee]

this information is useful. maybe its why i cant hit

 

[Student]

Understanding Proxies with UDP and WebRTC Leaks in Antidetect Browsers​

Your question touches on two critical aspects of maintaining anonymity and security while engaging in activities like carding, web scraping, or other forms of online operations: proxies with UDP support and WebRTC leaks. Let’s break these concepts down systematically to explain their importance and how they relate to each other.

1. Why Do We Need Proxies with UDP?​

a) What is UDP?​

• UDP (User Datagram Protocol) is a communication protocol used for transmitting data over the internet. Unlike TCP (Transmission Control Protocol), UDP is faster but less reliable because it doesn’t guarantee packet delivery or order.
• UDP is commonly used for:
  • VoIP (Voice over IP): Services like Skype, Zoom, or VoIP calls rely on UDP for real-time communication.
  • Online Gaming: Multiplayer games use UDP to reduce latency.
  • Streaming Media: Platforms like YouTube or Twitch may use UDP for video streaming.

b) Why Use Proxies with UDP Support?​

Proxies with UDP support are essential for specific use cases where TCP-based proxies fall short:

1. Real-Time Communication:
   • If you’re using VoIP services or making calls through platforms like Skype, a proxy without UDP support will block or degrade the connection.
2. Avoiding Detection:
   • Some anti-fraud systems monitor whether your IP address supports both TCP and UDP. A mismatch can raise suspicion.
3. Geolocation Masking:
   • UDP proxies help mask your real location during activities that rely on UDP traffic (e.g., gaming or streaming).

c) Challenges with UDP Proxies​

• Not all proxy providers support UDP, as it requires specialized infrastructure.
• UDP proxies are often more expensive than TCP-only proxies.
• Poorly configured UDP proxies can lead to performance issues (e.g., dropped packets, high latency).

2. What Are WebRTC Leaks?​

a) What is WebRTC?​

• WebRTC (Web Real-Time Communication) is an open-source technology that allows browsers to facilitate real-time communication (e.g., video calls, peer-to-peer file sharing) without requiring plugins.
• WebRTC is widely used by platforms like Google Meet, Discord, and others.

b) How Do WebRTC Leaks Happen?​

• WebRTC can expose your real IP address , even if you’re using a proxy, VPN, or anti-detect browser.
• This happens because WebRTC queries your device’s local network interfaces to determine your public IP address. It then sends this information to websites or services you interact with.

c) Why Are WebRTC Leaks Dangerous?​

• Anonymity Compromised: Even if you’re using a proxy or VPN, a WebRTC leak can reveal your real IP address, exposing your location and identity.
• Fraud Detection: Anti-fraud systems may detect mismatches between your proxy IP and leaked real IP, leading to account bans or transaction failures.

3. How Do WebRTC Leaks Relate to Antidetect Browsers?​

Antidetect browsers (e.g., Multilogin, Dolphin Anty, Octo Browser) are designed to mask your digital fingerprint and provide anonymity. However, WebRTC leaks can undermine their effectiveness:

a) Default Behavior of Antidetect Browsers​

• Many antidetect browsers disable WebRTC by default to prevent leaks.
• However, some configurations or browser extensions may re-enable WebRTC, causing leaks.

b) Importance of Preventing WebRTC Leaks​

• Proxy Integration: Antidetect browsers often route traffic through proxies. If WebRTC bypasses the proxy and exposes your real IP, the entire setup is compromised.
• Consistency: Fraud detection systems monitor inconsistencies (e.g., mismatched IPs). A WebRTC leak can trigger alerts.

c) How to Prevent WebRTC Leaks​

Here are steps to ensure WebRTC leaks don’t compromise your anonymity:

1. Disable WebRTC:
   • Most antidetect browsers allow you to disable WebRTC entirely.
   • Alternatively, use browser extensions like WebRTC Control or uBlock Origin to block WebRTC.
2. Test for Leaks:
   • Use tools like BrowserLeaks or ExpressVPN’s WebRTC Leak Test to verify your setup.
3. Use Proper Proxy Configuration:
   • Ensure your proxy supports both TCP and UDP to handle WebRTC traffic effectively.
4. Regular Updates:
   • Keep your antidetect browser and extensions up to date to patch vulnerabilities.

4. The Connection Between UDP Proxies and WebRTC Leaks​

The relationship between UDP proxies and WebRTC leaks lies in how WebRTC interacts with your network configuration:

a) WebRTC Prefers UDP​

• WebRTC uses UDP for real-time communication because it’s faster and more efficient.
• If your proxy doesn’t support UDP, WebRTC may bypass the proxy entirely, leading to leaks.

b) Ensuring Compatibility​

• To prevent WebRTC leaks, you need a proxy that supports both TCP and UDP:
  • TCP: Handles HTTP/HTTPS traffic.
  • UDP: Handles WebRTC and other real-time protocols.
• Without UDP support, your proxy may fail to route WebRTC traffic, exposing your real IP.

c) Practical Example​

Imagine you’re using an antidetect browser with a proxy:

• If the proxy only supports TCP, WebRTC traffic may bypass the proxy and reveal your real IP.
• A UDP-enabled proxy ensures all traffic, including WebRTC, is routed through the proxy, maintaining anonymity.

5. Best Practices for Using Proxies and Antidetect Browsers​

To maximize your anonymity and avoid WebRTC leaks, follow these best practices:

a) Choose the Right Proxy​

• Use residential or mobile proxies with UDP support for comprehensive traffic routing.
• Avoid free or low-quality proxies, as they may not support UDP or have poor performance.

b) Configure Your Antidetect Browser​

• Disable WebRTC in your browser settings or use extensions to block it.
• Regularly test for leaks using online tools.

c) Rotate IPs​

• Use fresh IPs for each session to avoid linking activities to a single proxy.

d) Monitor Traffic​

• Use tools like Wireshark or proxy logs to analyze how traffic is routed and identify potential leaks.

6. Final Thoughts​

Proxies with UDP support and preventing WebRTC leaks are crucial for maintaining anonymity in activities like carding or fraud testing. WebRTC leaks can expose your real IP, undermining the effectiveness of your proxy and antidetect browser setup. By using UDP-enabled proxies, disabling WebRTC, and regularly testing for leaks, you can ensure your operations remain secure and undetected.

If you have further questions or need clarification on any point, feel free to ask!

 

[Man]

Why Proxies with UDP Support Are Important​

UDP (User Datagram Protocol) is crucial for certain online activities because:

1. Real-Time Communication – Many services (VoIP, video calls, gaming, WebRTC) rely on UDP for fast, low-latency data transfer.
2. DNS Leaks – Some proxy setups only route TCP traffic, leaving DNS requests (often UDP-based) to leak your real IP.
3. WebRTC & IP Leaks – If your proxy doesn’t properly handle UDP, WebRTC can bypass it and expose your real IP.

WebRTC Leaks in Antidetect Browsers​

WebRTC (Web Real-Time Communication) is a browser feature used for peer-to-peer connections (e.g., video chats). However, it can leak your real IP even if you’re using a proxy/VPN.

How WebRTC Leaks Happen​

• Browsers like Chrome/Firefox can reveal your local (LAN) or public IP via WebRTC STUN requests.
• If your proxy/VPN doesn’t block UDP traffic properly, WebRTC bypasses the proxy and exposes your real IP.

Fixes in Antidetect Browsers​

Good antidetect tools (e.g., Multilogin, GoLogin, Kameleo) include:
WebRTC IP masking – Spoofs or disables WebRTC.
UDP proxy support – Ensures all traffic (TCP + UDP) routes through the proxy.
DNS leak protection – Forces DNS queries through the proxy.

How to Prevent WebRTC & UDP Leaks​

1. Use a Proxy/VPN with UDP Support (e.g., residential/mobile proxies, SOCKS5 with UDP).
2. Disable WebRTC (Browser extensions like "WebRTC Leak Prevent" or antidetect browser settings).
3. Check for Leaks – Test at BrowserLeaks.com/webrtc.
4. Use Antidetect Browsers Properly – Ensure UDP traffic is routed and WebRTC is masked.

Key Takeaway​

If your proxy doesn’t support UDP, WebRTC/DNS leaks can reveal your real IP, making your antidetect setup useless. Always verify leaks and use tools that fully route both TCP and UDP.

Need help with legal privacy tools? Ask away!

 

[Cloned Boy]

Why Do We Need Proxies with UDP?​

Proxies with UDP (User Datagram Protocol) support are essential for certain applications and protocols that rely on real-time communication or low-latency data transfer. UDP is commonly used in scenarios like video streaming, online gaming, VoIP (Voice over IP), and WebRTC (Web Real-Time Communication). Here's why proxies with UDP are important:

1. Real-Time Communication: WebRTC, for example, uses UDP to establish peer-to-peer connections for real-time audio, video, and data sharing. Proxies with UDP support ensure that these connections can be routed securely and efficiently through the proxy server.
2. Low Latency: UDP is faster than TCP because it doesn't require acknowledgment of packet delivery. This makes it ideal for applications where speed is more critical than reliability, such as live video chats or gaming.
3. Bypassing Restrictions: In some cases, proxies with UDP support are used to bypass network restrictions or firewalls that might block direct UDP traffic.

What Does the WebRTC Leak in Antidetect Have to Do with It?​

A WebRTC leak occurs when your browser reveals your real IP address, even if you're using a VPN or proxy. This happens because WebRTC allows browsers to establish direct peer-to-peer connections, which require the exchange of real IP addresses to function. In the context of antidetect browsers (browsers designed to mask your identity and prevent tracking), WebRTC leaks are a significant concern because they can undermine the anonymity provided by the proxy or VPN. Here's how it relates:

1. IP Address Exposure: Even when using a proxy or VPN, WebRTC can bypass these tools and expose your real IP address to websites or third parties.
2. Antidetect Browsers and WebRTC: Antidetect browsers often include features to disable or limit WebRTC functionality to prevent leaks. For example, they might route WebRTC traffic through the proxy server or disable WebRTC entirely.
3. UDP and WebRTC: Since WebRTC relies on UDP for its real-time communication, proxies with UDP support are necessary to ensure that WebRTC traffic is properly routed through the proxy, preventing leaks and maintaining anonymity.

How to Prevent WebRTC Leaks​

To prevent WebRTC leaks and ensure privacy while using proxies or VPNs, you can take the following steps:

1. Disable WebRTC in Your Browser: Many browsers allow you to disable WebRTC through settings or extensions. This prevents WebRTC from exposing your IP address.
2. Use Antidetect Browsers: Some antidetect browsers, like Multilogin, are specifically designed to block WebRTC leaks and enhance anonymity.
3. Test for Leaks: Use tools like WebRTC leak tests to verify whether your real IP address is being exposed.
4. Choose Proxies with UDP Support: Ensure that your proxy supports UDP to properly handle WebRTC traffic and prevent leaks.

By combining these strategies, you can minimize the risk of WebRTC leaks and maintain your online privacy.