iCloud Private Relay, Apple’s paid privacy feature that promises to mask your IP address while browsing Safari, can expose your real IP address to any website that uses or pretends to use passkeys, according to security researchers Tommy Mysk and Talal Haj Bakry. Apple is investigating the report.
The root cause is architectural, webKit hands WebAuthn authentication ceremonies to the operating system’s credential service rather than handling them inside the browser, and that OS-level request is issued directly from the device with no awareness of the proxy Safari has configured. Because the fetch never enters Private Relay’s proxied path, the destination server sees the device’s real IP address regardless of whether Private Relay is active.
The practical implication is significant, an attacker does not need to present a visible passkey prompt to exploit this: a website can trigger a WebAuthn request silently in the background, log the visitor’s real IP, and leave no indication anything happened. For users who pay for iCloud+ specifically to avoid that kind of tracking, the protection they believe they have is not in place.
Mysk and Haj Bakry identified two additional WebKit features capable of bypassing Private Relay’s protection, both introduced in recent iOS 26 releases:
- DNS prefetching, added in iOS 26, reveals a user’s real DNS servers.
- WebTransport, added in iOS 26.4, can show the device’s real IP address.
Because the vulnerability is baked into how WebKit itself handles these requests, the problem is not limited to Safari. Third-party browsers that rely on the WebKit engine are also affected, which means iPhone users who switched to Chrome, Firefox, or any other iOS browser expecting different behavior are just as exposed.
Security Bulletin: WebKit’s handling of passkeys can cause iCloud Private Relay to leak your device’s real IP address. The same behaviour affects all iOS browsers that rely on proxy connections to hide the device’s IP, including Psylo, Onion Browser, and other proxy or Tor… pic.twitter.com/BvCW3aYzHV
— Psylo: Privacy Browser & Proxy (@psylo_app) August 4, 2026
The researchers published a test website so users can verify whether their IP is leaking while Private Relay is active. Until Apple issues a fix, the most reliable mitigation is using a traditional VPN alongside or instead of Private Relay, since a VPN applies protection at the network layer rather than the browser layer and intercepts the credential service’s requests before they leave the device.
Private Relay is included with all iCloud+ tiers, which start at $0.99 per month for 50GB of storage, and Apple has consistently positioned it as one of the headline privacy benefits that justify the subscription. The feature routes Safari traffic through two separate internet relays so that no single party, not Apple, not the network provider, and not the destination site, can see both who you are and what you are browsing. That two-hop architecture is genuinely more privacy-preserving than a conventional VPN in some respects, but it is weaker in others precisely because it operates at the browser layer rather than the system level.
Passkeys, the credential standard that replaced passwords in Apple’s system starting with iOS 16 and macOS Ventura, have been rolled out broadly across Apple’s own services and adopted by major third-party sites including Google, GitHub, and PayPal. The growing prevalence of WebAuthn on the web means the attack surface for this leak is expanding, not shrinking. A site does not need to have legitimate passkey support to trigger the request; it only needs to initiate a WebAuthn ceremony, which any server can do silently.
Mysk and Haj Bakry have a consistent track record of surfacing Apple privacy issues that initially appear minor but carry significant real-world consequences, and Apple’s response pattern to their disclosures has generally followed the same path: acknowledgment, investigation, and an eventual silent fix in a point release.
