"For example, Flo Health uses OHTTP for their app's Anonymous Mode, and Apple's Private Cloud Compute uses OHTTP to disassociate AI inference requests from user identities."
"While most of the PCC system specifications are public, compiled binaries add a layer of opaqueness. There are no reproducible builds, and there are no symbols within those binaries, creating potential discrepancies between the specification and what is shipped to the user."
"Researchers have previously opened other proprietary Apple interfaces, such as AirDrop, Apple Watch, iCloud Private Relay, satellite communication, and more (Stute et al., 2019; Rollshausen et al., 2025; Kiesel and Classen, 2025; Classen et al., 2025). These works repeatedly show that, even though Apple makes significant efforts to secure its systems and add privacy features, the lack of public research leads to trivial mistakes that cause severe shortcomings in user privacy and security."
1744651630 | macOS Sends Locally-Served DNS Zones to iCloud Private Relay | <a href="https://developer.apple.com/forums/thread/780720" rel="nofollow">https://developer.apple.com/forums/thread/780720 | <a href="https://news.ycombinator.com/item?id=43683780">https://news.ycombinator.com/item?id=43683780 | 1 comment
1776183767 | iCloud Private Relay is not secure | <a href="https://webrtchacks.com/apples-not-so-private-relay-fails-with-webrtc/" rel="nofollow">https://webrtchacks.com/apples-not-so-private-relay-fails-wi... | <a href="https://news.ycombinator.com/item?id=47767673">https://news.ycombinator.com/item?id=47767673 | 1 comment
1785886306 | IP and DNS Leaks in WebKit Affecting Proxy Browsers and iCloud Private Relay | <a href="https://mysk.blog/2026/08/04/webkit-proxy-icloud-private-relay-ip-leak/" rel="nofollow">https://mysk.blog/2026/08/04/webkit-proxy-icloud-private-rel... | <a href="https://news.ycombinator.com/item?id=49176697">https://news.ycombinator.com/item?id=49176697 | 43 comments
1785949588 | iCloud Private Relay leaks real IP addresses | <a href="https://proton.me/blog/icloud-private-relay-ip-leak" rel="nofollow">https://proton.me/blog/icloud-private-relay-ip-leak | <a href="https://news.ycombinator.com/item?id=49185697">https://news.ycombinator.com/item?id=49185697 | 1 comment
1785952050 | Apple's 'Private Relay' Is Exposing Users' Real IP Addresses | <a href="https://www.404media.co/apples-private-relay-is-exposing-users-real-ip-addresses/" rel="nofollow">https://www.404media.co/apples-private-relay-is-exposing-use... | <a href="https://news.ycombinator.com/item?id=49186320">https://news.ycombinator.com/item?id=49186320 | 1 comment
1vuio0pswjnm7 · · focus · HN ↗
Flo Health
<a href="https://www.ftc.gov/news-events/news/press-releases/2021/06/ftc-finalizes-order-flo-health-fertility-tracking-app-shared-sensitive-health-data-facebook-google" rel="nofollow">https://www.ftc.gov/news-events/news/press-releases/2021/06/...
<a href="https://www.ftc.gov/enforcement/cases-proceedings/1923133/flo-health-inc" rel="nofollow">https://www.ftc.gov/enforcement/cases-proceedings/1923133/fl...
<a href="https://www.ftc.gov/system/files/documents/cases/192_3133_flo_health_complaint.pdf" rel="nofollow">https://www.ftc.gov/system/files/documents/cases/192_3133_fl...
<a href="https://www.cbsnews.com/news/facebook-reportedly-received-sensitive-health-data-from-apps-without-consent/" rel="nofollow">https://www.cbsnews.com/news/facebook-reportedly-received-se...
<a href="https://www.labaton.com/cases/frasco-v-flo-health-inc" rel="nofollow">https://www.labaton.com/cases/frasco-v-flo-health-inc
<a href="https://natlawreview.com/article/jury-finds-meta-liable-collecting-private-reproductive-health-data" rel="nofollow">https://natlawreview.com/article/jury-finds-meta-liable-coll...
1789644223 | Frasco v. Flo Health 3:21-cv-00757-JD Wiretap liability, Meta Platforms [pdf] | <a href="https://www.govinfo.gov/content/pkg/USCOURTS-cand-3_21-cv-00757/pdf/USCOURTS-cand-3_21-cv-00757-9.pdf" rel="nofollow">https://www.govinfo.gov/content/pkg/USCOURTS-cand-3_21-cv-00... | <a href="https://news.ycombinator.com/item?id=49739197">https://news.ycombinator.com/item?id=49739197 | 0 comments
<a href="https://www.cbc.ca/news/canada/british-columbia/flo-health-privacy-class-action-1.7137600" rel="nofollow">https://www.cbc.ca/news/canada/british-columbia/flo-health-p...
Apple Private Cloud Compute
Unlocking Apple's Private Cloud Compute: An Analysis of Privacy-Preserving Artificial Intelligence
Proceedings of the 19th ACM Conference on Security and Privacy in Wireless and Mobile Networks (WiSec 2026)
<a href="https://arxiv.org/html/2605.24239v1" rel="nofollow">https://arxiv.org/html/2605.24239v1
"While most of the PCC system specifications are public, compiled binaries add a layer of opaqueness. There are no reproducible builds, and there are no symbols within those binaries, creating potential discrepancies between the specification and what is shipped to the user."
"Researchers have previously opened other proprietary Apple interfaces, such as AirDrop, Apple Watch, iCloud Private Relay, satellite communication, and more (Stute et al., 2019; Rollshausen et al., 2025; Kiesel and Classen, 2025; Classen et al., 2025). These works repeatedly show that, even though Apple makes significant efforts to secure its systems and add privacy features, the lack of public research leads to trivial mistakes that cause severe shortcomings in user privacy and security."
For example, iCloud Private Relay
<a href="https://www.bloomberglaw.com/api/v1/public/download/X2K9PC2CAT8OPAH7MV2P5QMI0B?public_link=RICKMANvAppleIncDocketNo526cv08218NDCalAug062026CourtDocket" rel="nofollow">https://www.bloomberglaw.com/api/v1/public/download/X2K9PC2C...
1744651630 | macOS Sends Locally-Served DNS Zones to iCloud Private Relay | <a href="https://developer.apple.com/forums/thread/780720" rel="nofollow">https://developer.apple.com/forums/thread/780720 | <a href="https://news.ycombinator.com/item?id=43683780">https://news.ycombinator.com/item?id=43683780 | 1 comment
1776183767 | iCloud Private Relay is not secure | <a href="https://webrtchacks.com/apples-not-so-private-relay-fails-with-webrtc/" rel="nofollow">https://webrtchacks.com/apples-not-so-private-relay-fails-wi... | <a href="https://news.ycombinator.com/item?id=47767673">https://news.ycombinator.com/item?id=47767673 | 1 comment
1785886306 | IP and DNS Leaks in WebKit Affecting Proxy Browsers and iCloud Private Relay | <a href="https://mysk.blog/2026/08/04/webkit-proxy-icloud-private-relay-ip-leak/" rel="nofollow">https://mysk.blog/2026/08/04/webkit-proxy-icloud-private-rel... | <a href="https://news.ycombinator.com/item?id=49176697">https://news.ycombinator.com/item?id=49176697 | 43 comments
1785949588 | iCloud Private Relay leaks real IP addresses | <a href="https://proton.me/blog/icloud-private-relay-ip-leak" rel="nofollow">https://proton.me/blog/icloud-private-relay-ip-leak | <a href="https://news.ycombinator.com/item?id=49185697">https://news.ycombinator.com/item?id=49185697 | 1 comment
1785952050 | Apple's 'Private Relay' Is Exposing Users' Real IP Addresses | <a href="https://www.404media.co/apples-private-relay-is-exposing-users-real-ip-addresses/" rel="nofollow">https://www.404media.co/apples-private-relay-is-exposing-use... | <a href="https://news.ycombinator.com/item?id=49186320">https://news.ycombinator.com/item?id=49186320 | 1 comment