What is a DNS leak? Where to find them, how to fix and more …
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If you’re interested in staying safe online than you’ve probably heard that DNS leaks are a real security risk. But what are they, exactly, and how can you protect yourself? Every time you access a new website your system sends a DNS (Domain Name System) request to find the site’s server. These requests aren’t encrypted, which means your ISP, Wi-Fi hotspot owners, even snoopers hanging around your favorite coffeeshop might be able to log your browsing stalling a VPN encrypts your connection, reducing the chance that hackers can watch what you’re doing, but not all providers keep you DNS-leak-free. It’s important to check that you’re this article we’ll explain some DNS basics, how and where you’re at risk. We’ll talk about simple DNS leak tests which can highlight security holes in seconds, and if it turns out you’re vulnerable, give you some useful ideas on what to do is DNS? Accessing looks easy, just enter its domain name in your browser – but there’s a lot going on particular, for your browser to find TechRadar’s server, it has to translate the domain into the server’s IP magic happens via the Domain Name System (DNS. ) Your browser sends a request to a DNS server, asking it to look up (or whatever other site you’re trying to visit) and the server sends back the IP ‘s a clever scheme, but has some privacy problems. For instance, devices normally use your ISP’s DNS server, which means it’s possible for the company to see and log where you’re going online. Connect to public Wi-Fi and it gets worse. Even if you’re accessing an encrypted website, your DNS request is usually plain text, so other hotspot users might be able to spy on the sites you’re visiting. And if that’s not worrying enough, a malicious hotspot could force you to use its own DNS server, log your internet activities, maybe even redirect you to phishing or other fake sites. (Image credit:)What is a DNS leak? Installing the best VPN allows your device to route its DNS requests (and all its other internet traffic) through a secure connection. Banking-grade encryption hides your web activities from your ISP, hotspot operators and others, as well as shielding you from pesky hotspot, that’s the theory. In reality, it’s not always that simple. A ‘DNS leak’ happens when a VPN doesn’t properly protect you, and your DNS queries, browsing history and maybe your device IP address are exposed to bad news is you’ll probably have no idea any of this is happening. In fact, as you’ve installed a VPN, you’ll probably think you’re entirely good news is testing for a DNS leak is easy, and you can check your system within a few do I know if I have a DNS leak? There are plenty of free DNS leak testing websites around, and the best do a great job of pointing out any privacy your VPN disconnected, go to and tap Extended Test. Make a note of the DNS server IP addresses listed in the test nnect to the VPN on the device you’ll use most often and run the test again. If you see new DNS servers which don’t belong to your ISP, the connection is secure. But if you still see some or all of your ISP DNS servers, you probably have a DNS confirm this, check the same device at a couple of other testing sites. BrowserLeaks, IPLeak and ipx are fast and deliver a stack of extra privacy details. (Passing (or failing) a test on an iPhone doesn’t mean you’ll see the same result on a Windows laptop or an Android phone, so we’d also recommend repeating the same leak test on every device you’ll connect to the network – whether that’s via an Android VPN, iPhone VPN or something else. )(Image credit:)How can I fix a DNS leak? It’s hard to believe, but although most VPNs have some form of DNS leak protection, they don’t always enable it by default. Open your app’s Settings panel, look for an option like ‘DNS leak protection’ and make sure it’s turned on. Enable ‘IPv6 Leak Protection’, too, if it’s available, and look for and turn on any setting which forces the use of the VPN’s own DNS servers. Search the VPN’s support site for useful a last resort, you could try changing your VPN app’s protocol (this is the method the VPN uses to connect to its servers. ) Some protocols have their own versions of DNS leak protection, so if one fails, another might work. Go back to your app Settings panel and try a different protocol, if you have the option. Flipping every possible app switch probably isn’t a good idea, of course, so only make tweaks when they look promising. And whenever you change something, make a note, so you can restore the original setting if it doesn’t work, or you notice other problems. (Changing protocol might fix a DNS leak but also slow you down, for instance. )If none of this helps, maybe it’s time to switch to a VPN which doesn’t have a DNS leak. NordVPN and ExpressVPN always deliver leak-free results in our more:Change location with a VPN: step-by-stepSave money with the best cheap VPNFree VPNs: are they good enough and which is the best?
Mike began his career as a lead software developer in the engineering world, where his creations were used by big-name companies from Rolls Royce to British Nuclear Fuels and British Aerospace. He now covers VPNs, antivirus and all things security for TechRadar, although he still has a secret love of quirky open-source and freeware apps which find brand new ways to solve common problems.
can I fix a DNS leak
The solution is to ensure that once connected to the VPN,
you are using ONLY the DNS server/s provided by the VPN service.
OpenVPN v2. 3. 9+
As of OpenVPN version 2. 9 you can now prevent DNS leaks by specifying a new OpenVPN option. Simply open the
(or) file for the server that you are connecting to
and add the following on a new line. For more information see the OpenVPN manual.
block-outside-dnsIf for any reason you are unable to use the solution above continue reading.
If you are using a version of OpenVPN older than v2. 9
Please note that as this problem normally only affects windows clients, only solutions for Windows appear
here.
3 basic steps to fix the problem;
Before connecting to the VPN, set static IP address properties if you are using DHCP
After connecting, remove DNS settings for the primary interface
After disconnecting, switch back to DHCP if neccessary or reapply original static DNS servers
Solution A – Automatic
If you are using OpenVPN on Windows XP/Vista/7 then a fully automated solution is available.
Download – (md5 checksum:
f212a015a890bd2dae67bc8f8aa8bfd9)
After installation, when you connect to a VPN server, a batch file will be run executing the 3 steps
above.
Three scripts are generated for each OpenVPN configuration file;
– executed when you initiate the connection but before the
connection is established – Calls – If any active DHCP adapters exist, switch to static
– executed when the connection is established – Calls –
Clear the DNS servers for all active adapter except the TAP32 adapter
– executed after the connection is disconnected – Calls
– Reconfigure adapters back to their original configuration
Solution B – Manually clearing the DNS
The solution below does not switch the adapter to static if you are using DHCP. If you do not
switch to a static IP configuration and your computer renews its IP address whilst connected to
the VPN, the DNS settings may be overwritten. It is highly recommended to switch to a static
IP configuration.
Open the command prompt () as an administrator.
Before connecting identify the name of the connected network interface. In the case below it is
“Local Area Connection”
netsh interface show interface
Connect to the VPN. Once connected proceed to the next step.
Flush the DNS resolver cache
ipconfig /flushdns
Disable the DNS configuration for the Interface identified in step 1
netsh interface IPv4 set dnsserver “Local Area Connection” static 0. 0. 0 both
Test for DNS leaks.
After disconnecting, reconfigure the adapter to renew the previous DNS settings
netsh interface IPv4 set dnsserver “Local Area Connection” dhcp
Once again, flush the DNS resolver cache.
Done.
Is Your VPN Leaking? | PCMag
Just how secure is your private data? You may think you have a Fort Knox-like setup, but don’t take risks with your personal info. It’s worth confirming that the virtual private network, or VPN, software you use is actually doing its job, or if it’s allowing your personal data to go hither and thither without your knowledge.
For the most part, if you pick one of our top VPN services, you’ll be well protected, be it on a PC or even a smart device (most of the best services offer software across all operating systems). But it never hurts to check. Things break, new exploits are found, and there’s always a chance your VPN may be leaking more data than you prefer. Here are some steps you can take to see if that’s true.
Check Your IP Address
Your home has an IP address, not just a street address. The IP (internet protocol) address is the unique number assigned to your router by your ISP. (Your internal home network in turn gives each node in your home—PCs, phones, consoles, smart appliances, anything connected to the router—an IP address. But in this case, we’re only concerned with your public-facing IP address. )
The IP address is how your computers/router talk to servers on the internet. They don’t use names—like —because computers prefer numbers. IP addresses are typically bound not only to the ISPs that assign them, but also specific locations. Spectrum or Comcast have a range of IP addresses for one town and a different range for another town, etc.
When someone has your IP address, they get a lot more than just some numbers: they can narrow down where you live.
IP addresses come in several formats, either a IPv4 (internet protocol version 4) version like 172. 16. 254. 1 or an IPv6 type that looks like 2001:0db8:0012:0001:3c5e:7354:0000:5db1.
Let’s keep it simple. Your own public-facing IP address is easy to find. Go to Google and type “what’s my IP address. ” Or go to sites like Tenta Browser Privacy Test, IPLocation,, or They’ll display more than your IP; they’ll also give you the Geo-IP—the location linked to the address.
Take the IP address that comes up and search for it in Google with IP in front, like “IP 172. 1” (sans quotation marks). If it keeps coming up with your city location, your VPN has a big, messy leak.
The leak could be caused by what’s known as the WebRTC bug; WebRTC is a collection of standards that look hard to find your IP address, to make things go faster when you use the internet and services like video chat and streaming. If you’ve got a modern desktop browser, you’re likely to have this, as the browsers all enable WebRTC to work better. You can check with the Hide My Ass WebRTC Leak Test.
VPNs that work via an extension in a browser will turn it off, among other things. Or disable WebRTC in browsers directly yourself.
Chrome Requires an extension like WebRTC Network Limiter or WebRTC Leak Prevent, or try WebRTC Control to toggle it on and off from the toolbar.
EdgeYou can’t really fix it, but you can hide your local IP address entirely by typing “about:flags” and checking the box next to “Hide my local IP address over WebRTC connections. ” It probably hurts you with location services more than it helps protect you.
Safari It shouldn’t be an issue, as Apple’s browser doesn’t share like the rest.
Firefox Type “about:config, ” click on the “I accept the risk! ” button, type “erconnection. enabled” in the search box, then double-click to change to the Value column to say False.
Opera Go to View > Show Extensions > WebRTC Leak Prevent > Options. Choose to disable it and save the settings.
Check for DNS Leaks
The internet domain name system (DNS) is what makes IP addresses and domain names (like “”) work. You type the domain name into a web browser, the DNS translates all the traffic moving back and forth from your browser to the web server using the IP address numbers, and everyone is happy.
ISPs are part of that—they have DNS servers on their networks to help with the translation, and that gives them another avenue to follow you around. This video from ExpressVPN spells it out (and tells you why a VPN with DNS services on their servers is great).
Using a VPN means, in theory, your internet traffic is redirected to anonymous DNS servers. If your browser just sends the request to your ISP anyway, that’s a DNS leak.
There are easy ways to test for a leak, again using websites like Hidester DNS Leak Test,, or DNS Leak You’ll get results that tell you the IP address and owner of the DNS server you’re using. If it’s your ISP’s server, you’ve got a DNS leak., in particular, gives you a nice color-coded result, with “Looks like your DNS might be leaking… ” in red, or green if you appear to be in the clear. Hidester gives you a full list of every DNS server you may hit. When several correspond to your actual ISP, that better underscores your leaky-ness.
Fix the Leaks
If you do have a leak, you have a couple options. One, change your VPN to one that specifically works to prevent DNS leaks. All our Editors’ Choice picks—Private Internet Access VPN, NordVPN, and TunnelBear—promise to be leak-free.
If you like your current VPN too much to switch, maybe buy Guavi’s VPNCheck Pro for $19. 92. It has its own DNS leak fix, and monitors your VPN for other issues.
Recommended by Our Editors
You can also change the DNS servers used by your router when you send requests to the internet. This can be a little complicated as it requires you to go into the settings for your router, but might be worth it for other reasons. Services like Google Public DNS or Cisco’s OpenDNS provide instructions on how to set them up with most routers. The latter has a personal version with various free options, even one geared specifically to family/parental controls that block questionable sites. You can pay $19. 95/year for extra services like usage stats and whitelists of sites under the OpenDNS Home VIP option.
There’s even a DNS service specifically for mobile devices: Cloudflare’s 1. 1. It not only encrypts DNS queries but promises faster internet. It can also be configured to work with routers and PCs, however. (Learn more in our recent interview with Cloudflare CTO John Graham-Cumming. )
Making a DNS update to your router means all the traffic in your home or office uses the new DNS service and whatever ancillary features it provides. That includes PCs, phones, tablets, consoles, even smart speakers, you name it.
With these services, you’re handing your DNS traffic over to another corporation. You could instead invest in hardware at the router level to add extra security, but that may be overkill if you’re not feeling terminally paranoid. At the very least, on individual PCs and handheld devices, get VPN software/apps for supplemental security all around.
Plug Other Leaks
Your location is probably something you’ve plugged into your browser at some point. If so, your browser is typically more than willing to share that information with the websites you visit, even if your VPN does not. Check the massive amount of data you may be giving up by visiting
Use an alternative browser when you want to be at your most secure—the Tor Browser, for example. It’s all about keeping you anonymous, by bouncing your requests around the world before they land on the web server you want, then back again. That makes it hard for you to find your local info and can slow things down overall, but it’s a good bet for security.
If you can’t stand the thought of giving up your current browser, use incognito mode, go the complicated route of setting up a fake location, or just get an extension like Location Guard (for Chrome, Opera, or Firefox) to spoof your whereabouts.
If you’re worried about your web-based email system, switch to ProtonMail. Not only does it redirect messages over the Tor network, it keeps everything encrypted. (For more, read How to Create an Anoymous Email Account. ) Proton Technologies also offers ProtonVPN for Mac, Windows, Linux, and Android. There is a tier of service that’s free forever for one device—including DNS leak protection—while the paid versions support Tor servers and more.
Disclosure: PCMag’s parent company Ziff Davis is owned by j2 Global, which also owns various software products and services including, IPVanish, andStrongVPN.
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Frequently Asked Questions about dns leak android
How do I fix a DNS leak?
3 basic steps to fix the problem;Before connecting to the VPN, set static IP address properties if you are using DHCP.After connecting, remove DNS settings for the primary interface.After disconnecting, switch back to DHCP if neccessary or reapply original static DNS servers.
Do I have a DNS leak?
There are easy ways to test for a leak, again using websites like Hidester DNS Leak Test, DNSLeak.com, or DNS Leak Test.com. You’ll get results that tell you the IP address and owner of the DNS server you’re using. If it’s your ISP’s server, you’ve got a DNS leak.
What is a leaking DNS server?
A DNS leak is a security flaw that occurs when requests are sent to an ISP’s DNS servers even when a VPN is being used to protect users. … As a result, all their browsing activity, including their IP address, location, and web searches, goes through the ISP in the same way it would if they were not using a VPN.