iOS Vulnerability Prevents VPNs From Encrypting All Traffic

A vulnerability affecting iOS 13.3.1 and later prevents virtual private networks (VPNs) from encrypting all traffic, allowing some internet connections to bypass encryption, potentially exposing users' data and IP addresses.

ios device network ip wireshark

A screenshot from ProtonVPN demonstrating exposed connections to Apple's servers that should be protected by the VPN

Details on the vulnerability were shared today by Bleeping Computer after it was discovered by ProtonVPN. The vulnerability is caused because iOS isn't terminating all existing connections when a user connects to a VPN, allowing them to reconnect to destination servers once the VPN tunnel has been established.

Connections made after connecting to a VPN on an iOS are not affected by this bug, but all previously established connections are not secure. This could potentially lead to a user who believes they are protected accidentally exposing IP an address and therefore, an approximate location.

Apple's Push Notifications are cited as an example of a process using connections on Apple's servers that aren't closed automatically when connecting to a VPN, but it can affect any app or service running on a user's device.

VPNs cannot work around the issue because iOS does not allow VPN apps to kill existing network connections, so this is a fix that will need to be implemented by Apple. Apple is aware of the vulnerability and is looking into options to mitigate it.

Until fixed, VPN users can connect to a VPN server, turn on Airplane Mode and then turn off Airplane Mode to kill all existing connections. The mitigation isn't entirely reliable, however, so iPhone and iPad owners who rely on VPNs should be careful until Apple puts out a fix.

Popular Stories

iOS 26

15 New Things Your iPhone Can Do in iOS 26.2

Friday December 5, 2025 9:40 am PST by
Apple is about to release iOS 26.2, the second major point update for iPhones since iOS 26 was rolled out in September, and there are at least 15 notable changes and improvements worth checking out. We've rounded them up below. Apple is expected to roll out iOS 26.2 to compatible devices sometime between December 8 and December 16. When the update drops, you can check Apple's servers for the ...
Intel Inside iPhone Feature

Apple's Return to Intel Rumored to Extend to iPhone

Friday December 5, 2025 10:08 am PST by
Intel is expected to begin supplying some Mac and iPad chips in a few years, and the latest rumor claims the partnership might extend to the iPhone. In a research note with investment firm GF Securities this week, obtained by MacRumors, analyst Jeff Pu said he and his colleagues "now expect" Intel to reach a supply deal with Apple for at least some non-pro iPhone chips starting in 2028....
iPhone 14 Pro Dynamic Island

iPhone 18 Pro Leak Adds New Evidence for Under-Display Face ID

Monday December 8, 2025 4:54 am PST by
Apple is actively testing under-screen Face ID for next year's iPhone 18 Pro models using a special "spliced micro-transparent glass" window built into the display, claims a Chinese leaker. According to "Smart Pikachu," a Weibo account that has previously shared accurate supply-chain details on Chinese Android hardware, Apple is testing the special glass as a way to let the TrueDepth...
iOS 26

Apple Seeds Second iOS 26.2 Release Candidate to Developers and Public Beta Testers

Monday December 8, 2025 10:18 am PST by
Apple today seeded the second release candidate version of iOS 26.2 to developers and public beta testers, with the software coming one week after Apple seeded the first RC. The release candidate represents the final version iOS 26.2 that will be provided to the public if no further bugs are found. Registered developers and public beta testers can download the betas from the Settings app on...
iPhone 17 Pro Cosmic Orange

10 Reasons to Wait for Next Year's iPhone 18 Pro

Monday December 1, 2025 2:40 am PST by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models at the same time, which is why we often get rumored features months ahead of launch. The iPhone 18 series is no different, and we already have a good idea of what to expect for the iPhone 18 Pro and iPhone 18 Pro Max. One thing worth...
Johny Srouji

Apple's Chipmaking Chief Johny Srouji Responds to Report About Him Potentially Leaving

Monday December 8, 2025 9:23 am PST by
Apple's chipmaking chief Johny Srouji has reportedly indicated that he plans to continue working for the company for the foreseeable future. "I love my team, and I love my job at Apple, and I don't plan on leaving anytime soon," said Srouji, in a memo obtained by Bloomberg's Mark Gurman. Here is Srouji's full memo, as shared by Bloomberg:I know you've been reading all kind of rumors and...
Johny Srouji

Apple Chip Chief Johny Srouji Could Be Next to Go as Exodus Continues

Sunday December 7, 2025 10:41 am PST by
Apple's senior vice president of hardware technologies Johny Srouji could be the next leading executive to leave the company amid an alarming exodus of leading employees, Bloomberg's Mark Gurman reports. Srouji apparently recently told CEO Tim Cook that he is "seriously considering leaving" in the near future. He intends to join another company if he departs. Srouji leads Apple's chip design ...
google pixel 10

Switching Between iPhone and Android Will Get Easier With New Apple and Google Collaboration

Monday December 8, 2025 11:10 am PST by
Apple and Google are teaming up to make it easier for users to switch between iPhone and Android smartphones, according to 9to5Google. There is a new Android Canary build available today that simplifies data transfer between two smartphones, and Apple is going to implement the functionality in an upcoming iOS 26 beta. Apple already has a Move to iOS app for transferring data from an Android...
Apple Fitness Plus expansion hero

Apple Fitness+ Coming to 28 New Regions With Digital Voice Dubbing

Monday December 8, 2025 6:19 am PST by
Apple today announced that Fitness+ is expanding to 28 new markets on December 15 in the service's largest international rollout since launch, accompanied by new language dubbing and a K-Pop music genre. Apple Fitness+ will become available in Chile, Hong Kong, India, the Netherlands, Singapore, Taiwan, and additional regions on December 15, with Japan scheduled to follow early next year....
maxresdefault

iPhone Fold: Launch, Pricing, and What to Expect From Apple's Foldable

Monday December 1, 2025 3:00 am PST by
Apple is expected to launch a new foldable iPhone next year, based on multiple rumors and credible sources. The long-awaited device has been rumored for years now, but signs increasingly suggest that 2026 could indeed be the year that Apple releases its first foldable device. Subscribe to the MacRumors YouTube channel for more videos. Below, we've collated an updated set of key details that ...

Top Rated Comments

Will Tisdale ? Avatar
75 months ago

This is 100% fake and not a bug. All VPNs, such as those on the desktop, do this by default unless specifically configured, as to not interrupt ongoing downloads, or worse, cause UDP-based services to silently fail.
I don’t think so.
iOS used to handle this correctly, then stopped.
Not tearing down existing connections completely undermines the point of a VPN.
Score: 11 Votes (Like | Disagree)
Will Tisdale ? Avatar
75 months ago

Nope. I have two full tunnels on two different clients (Cisco Anyconnect, and Pulse Secure)
Well, I can tell you that Anyconnect will tear down any active connections, assuming it’s configured correctly. My work VPN certainly does.

TCP is designed to retry after being torn down. It’s no biggie.

The fact is, this is an iOS bug, which was introduced recently.
Score: 5 Votes (Like | Disagree)
konqerror Avatar
75 months ago
This is 100% fake and not a bug. All VPNs, such as those on the desktop, do this by default unless specifically configured, as to not interrupt ongoing downloads, or worse, cause UDP-based services to silently fail. Windows built-in VPN client has this exact same behavior.
Score: 3 Votes (Like | Disagree)
Westside guy Avatar
75 months ago
I’m sometimes stunned by the upvotes people get for posting incorrect information.

If a VPN is configured to send all network traffic through the VPN when it’s running - which is typically what‘s done - then all traffic should be routing through it from the moment it’s enabled. Not just connections to new end points established afterward - all traffic.

Even if a VPN is configured to just carry traffic to a few specific end points (such as the OpenVPN tunnel to our servers, which I’m relying on heavily right now due to the stay at home order currently in place here in Washington): if you’re already connected to one of those end points before establishing the tunnel, you would expect all further traffic to go through the tunnel. The idea that you wouldn’t is ludicrous.
Score: 3 Votes (Like | Disagree)
Will Tisdale ? Avatar
75 months ago

I feel like we need more info here.

As others have said, it would be problematic to silently kill existing connections when connecting to a VPN. That's certainly not the behavior I would expect. I suppose it depends on whether you use a VPN to add certain networks (such as your corporate office), or to globally route all your traffic (such as for privacy reasons). In the former case, I don't want my non-office connections to be reset.

If MacRumors is reporting this right and VPN apps cannot reset connections, that makes me wonder what changed here. Did iOS previously indeed terminate any open socket when connecting?
I feel that people need to learn about the expected behaviour of VPNs before commenting.
There’s actually two types on iOS. Split vpn and full tunnel. Split allows some stuff to be routed elsewhere. Full tunnel tunnels everything.
Score: 3 Votes (Like | Disagree)
Square-Eyes Avatar
75 months ago
I got caught out by the fact that if you tether a device to your phone it will bypass the phone’s VPN ??‍♂️
Score: 2 Votes (Like | Disagree)