Security firm Calif.io demonstrated a permanent, untethered jailbreak on an iPhone 18 Pro running iOS 27.0.1 at the Hexacon security conference in Paris on October 16, according to Decrypt. The demonstration showed root access returning after the phone was restarted, a result that highlights the continuing difficulty of securing fully updated devices against sophisticated exploit chains.
What Calif demonstrated
During the presentation, the team restarted the iPhone, unlocked it with the device’s ordinary passcode and opened an SSH session with root privileges. Root is the highest level of access on the phone. The terminal displayed iOS 27.0.1 and showed that the device had been running for roughly two minutes.
The jailbreak was described as “untethered,” meaning it remained available after a reboot without requiring the phone to be connected to a computer. That distinguishes it from jailbreaks that must be reapplied whenever a device restarts. Calif said the demonstration took place on an iPhone 18 Pro, making it a current example involving Apple’s latest hardware and software listed in the source material.
Apple designs iOS as a restricted system. Applications operate inside sandboxes, software is checked through code-signing protections and the startup process verifies the code that loads when the phone powers on. A jailbreak defeats some or all of those restrictions and gives the user control that Apple normally withholds.
With that access, users can install applications outside the App Store, inspect the full file system, remove unwanted preinstalled software, change the interface and add functions that Apple has not approved. Jailbreaks were more common during the early iPhone era, when they enabled capabilities such as video recording before Apple officially added the feature. They have also been used to install themes, unlock carriers and run Android on iPhones.
The vulnerabilities remain undisclosed
Calif.io has not identified the vulnerabilities used in the presentation and has not released a public jailbreak tool. Its conference newsletter listed four demonstrations, including a one-click Signal demonstration and an iMessage demonstration, and said the material would be released later.
That timing is important because an exploit chain capable of obtaining root access on a fully updated iPhone can have implications beyond customization. Building such a chain generally requires multiple weaknesses: one to escape an application’s sandbox, another to gain control of the kernel and additional work to get around hardware-backed protections, including Pointer Authentication Codes, which are designed to detect manipulation of memory pointers.
Remaining active after a reboot adds another obstacle. Apple’s startup process checks the code that is allowed to run, so a jailbreak that persists through restarting must overcome protections that a temporary exploit can avoid. The demonstration therefore showed more than an app-level flaw, although Calif has not disclosed the technical path it used.
A root-level capability on a current iPhone is also the type of access associated with commercial spyware operations sold to governments. Apple typically patches exploit chains after learning their details. The period during which iOS 27.0.1 remains vulnerable will depend substantially on when Calif publishes its findings and on Apple’s response.
Apple security notes and AI involvement
Apple has not publicly commented on the conference demonstration. The company’s stated practice is not to confirm security issues until patches are available.
Apple’s iOS 27 security notes, published on September 14, credit Calif.io, working with Claude and Anthropic Research, for two unrelated bugs. Those issues allowed an application to cause a denial of service or a system crash. The notes do not connect either bug to the jailbreak shown at Hexacon.
Calif’s previous descriptions have also linked Anthropic’s Claude systems to security research. In April, Calif’s Thai Duong wrote about using Claude to analyze an iOS Safari exploit. In May, Calif said Anthropic’s Claude Mythos Preview helped build a macOS kernel exploit targeting protections for Apple’s M5 chip in less than a week. Calif said the exploit chain was not developed alone and that Mythos Preview helped identify bugs and supported development.
Current market picture
Moneyiar market data at the stated times showed the following prices and performance:
- Ethereum (ETH): $2379.3173412276, down 1.42% over 24 hours and 5.09% over seven days, as of 2026-10-17 21:49:00 +03:30.
- Tether USDt (USDT): $0.9987418022, up 0.02% over 24 hours and down 0.04% over seven days, as of 2026-10-17 21:48:00 +03:30.
- Tagger (TAG): $0.0005507388, down 5.14% over 24 hours and 14.1% over seven days, as of 2026-10-17 21:49:00 +03:30.
- ONEchain (ONE): $0.099968065, down 4.41% over 24 hours and 26.15% over seven days, as of 2026-10-17 21:48:00 +03:30.
The Hexacon event continues through October 17 in Paris. Calif has not said when it will release the jailbreak details, leaving the technical scope of the demonstration and the potential patch timeline unresolved.
