Apple fixed an old iOS bug that let nearby wireless routers gather real MAC addresses even when Private Wi-Fi Address is enabled, including in Lockdown Mode
“From the get-go, this feature was useless,” researcher says of feature put into iOS 14. — Three years ago, Apple introduced …
Ars TechnicaDan Goodin
Context & Ripple Effects
Apple’s Private Wi‑Fi Address feature was meant to limit device identification on local networks, but the newly fixed flaw meant nearby routers could still obtain the hardware MAC address—even under Lockdown Mode. That turns a privacy control into an incomplete boundary rather than a reliable one.
iPhone users receiving the fix regain the intended separation between a network-facing randomized address and the device’s real MAC address on nearby Wi‑Fi infrastructure.
Network operators and anyone operating nearby wireless routers lose an avenue to associate affected iOS devices with a stable hardware identifier while the privacy setting is enabled.
Second-order effects
The finding raises the bar for Apple’s privacy-feature validation: protections advertised as usable in Lockdown Mode must be tested against lower-level Wi‑Fi behavior, not only app- and OS-level controls.
Organizations that rely on MAC-based Wi‑Fi identification may see less consistent device recognition as patched iPhones stop exposing their permanent address in this scenario.
Third-order effects
The episode reinforces that wireless privacy depends on implementation across the networking stack; randomized identifiers provide limited protection when underlying protocol behavior can reveal a stable identifier.
If similar gaps continue to surface, privacy modes will increasingly be judged on measurable resistance to local-network tracking rather than on the presence of a setting alone.
The trend: Consumer platforms are moving from privacy controls as interface features toward privacy controls that must hold up against network-layer identification techniques.
“On Wednesday, the world learned that the feature has never worked as advertised.” — Where have we heard that before? Oh, let's see, how about macOS App Management, for example. — Apple is very good at security theater. — https://arstechnica.com/...
“Apple hasn't explained how a failure as basic as this one escaped notice for so long. The advisory the company issued Wednesday said only that the fix worked by ‘removing the vulnerable code.’” https://arstechnica.com/...
‘Three years ago, Apple introduced a privacy-enhancing feature that hid the Wi-Fi address of iPhones and iPads when they joined a network. On Wednesday, the world learned that the feature has never worked as advertised.’ https://arstechnica.com/...
Despite promises that this never-changing address would be hidden and replaced with a private one that was unique to each SSID, Apple devices have continued to display the real one, which in turn got broadcast to every other connected device on the network https://arstechnica.com…
This new iPhone flaw is about tracking users *while connected* to a Wi-Fi network. Even with the CVE fixed, that's IMO hard to fully prevent. Usage of random MAC addresses while *scanning* for Wi-Fi networks seems to have properly worked all the time. https://arstechnica.com/...
@UK_Daniel_Card Ohh yeah, I'm confusing two things before coffee. There was a cve patched with 17.1 where devices with Private (MAC) Address set to on, leaked their true MAC address on 5353 anyway. Not IP. (Intrigued how LinkedIn can bypass private relay though.) https://arstechn…
“Three years ago, Apple introduced a privacy-enhancing feature that hid the Wi-Fi address of iPhones and iPads when they joined a network. On Wednesday, the world learned that the feature has never worked as advertised.” https://arstechnica.com/...
NEW: Private Wi-Fi addresses had been useless ever since they were introduced in iOS 14. When an iPhone joins a network, it sends multicast requests to discover AirPlay devices in the network. In these requests, iOS sends the device's real Wi-Fi MAC address. Exposure of a devi…
iPhones have been exposing your unique MAC despite Apple's promises otherwise — “From the get-go, this feature was useless,” researcher says of feature put into iOS 14
iPhones have been exposing your unique MAC despite Apple's promises otherwise | “From the get-go, this feature was useless,” researcher says of feature put into iOS 14.
iPhones have been exposing your unique MAC despite Apple's promises otherwise | “From the get-go, this feature was useless,” researcher says of feature put into iOS 14.