Security researchers Talal Haj Bakry and Tommy Mysk have found problems in Apple's web engine that can cause iCloud Private Relay to stop hiding your real IP address from websites. The findings, published on the researchers' blog on August 4, 2026, were independently verified by 404 Media and have since been acknowledged by Apple, which told 404 Media it is investigating the report (Engadget).

Private Relay is an optional iCloud+ feature that hides your IP address while browsing in Safari. Your IP address is a number that identifies your device on the internet, and websites can use it to figure out your general location. Private Relay works like a middleman: it sends your Safari browsing through relay servers so the website sees the relay's address, not yours. But as TechCrunch described in its coverage, the feature can be circumvented to leak the user's real IP address (TechCrunch). The problem is that Private Relay only covers Safari's normal web traffic. It does not work like a full-device VPN that protects everything your phone does online. Any connection that Apple's web engine, called WebKit, makes outside of normal web browsing bypasses Private Relay entirely.

The researchers found two specific ways this happens. The first involves passkeys, which are a newer, safer replacement for passwords. When you use a passkey to sign in to a website in Safari, WebKit sends an authentication request outside the browser's normal web traffic. Because Private Relay only protects Safari's web traffic, that request carries your device's real IP address. The website or service receiving it can therefore learn your actual IP even though Private Relay is turned on (Engadget; mysk.blog).

The second way involves WebTransport, a technology for direct connections between a browser and a server. WebKit sets up this connection outside the web traffic that Private Relay protects, so a WebTransport server can see your device's real IP address directly (mysk.blog).

Because the flaw is in WebKit rather than in Safari specifically, the problem extends beyond Apple's own browser. All browsers on the iPhone are required to use WebKit under Apple's rules. That means privacy-focused browsers, including OnionBrowser and the researchers' own Psylo browser, are also affected when passkeys are used (Engadget). The researchers stated in a post on X that they had contacted OnionBrowser and the Tor Project to share their findings and possible solutions.

The researchers also pointed to a past example to set expectations about how long a fix might take. Another research team discovered a vulnerability in iCloud Hide My Email in mid-2025; Apple did not fix that issue for about a year (Engadget; 404 Media). The implication is that fixes for the Private Relay leak may not arrive quickly, even with Apple now actively investigating.

The broader context here is a tension built into how Private Relay was designed. Apple made it as a lightweight privacy layer for Safari, not as a full system-wide VPN. That choice keeps your browsing fast and avoids draining your battery or causing compatibility problems. But it also means that any part of WebKit that opens a connection outside the protected path, whether for passkey sign-ins or WebTransport, is completely outside what Private Relay covers. The feature's privacy promise is only as strong as the narrowest definition of "Safari web traffic."

For iPhone users who rely on privacy-focused browsers specifically to avoid IP exposure, the passkey problem is especially serious. Someone who opens OnionBrowser expecting Tor-level privacy can still leak their real IP address the moment they sign in with a passkey, because the underlying WebKit engine handles that sign-in outside both the Tor network and Private Relay's protection. Switching browsers does not help.

This also raises questions about how two of Apple's key privacy features work together. Passkeys are designed as a safer replacement for passwords, and Private Relay is designed to protect your browsing privacy. Both work fine on their own. The leak happens where they meet, because WebKit's handling of passkey sign-ins creates a traffic path that neither feature accounts for.

The practical takeaway is straightforward. Private Relay should not be relied on as a complete IP-hiding solution on the iPhone, especially for users who sign in with passkeys or visit websites using WebTransport. A full-device VPN or Tor remains the stronger option when hiding your IP address is a must. Until Apple releases a fix, the gap between what Private Relay promises and what it actually covers is something users and security teams should keep in mind.