FBI extraction of deleted Signal messages: Apple secures iPhones better
iOS stored messages marked for deletion – including those from crypto messengers – in a readable database. This should no longer happen.
(Image: Primakov/Shutterstock.com)
Quickly pushed security patch for iOS 26 and iOS 18: Apple released iOS / iPadOS 26.4.2 and iOS / iPadOS 18.7.8 for download for all supported devices on Thursday night. As usual, the manufacturer only vaguely mentions bug fixes and security improvements in the release notes.
FBI was able to extract Signal messages
According to the documentation, the new versions only fix a single vulnerability, which however recently caused considerable consternation: According to court documents, FBI investigators could read deleted Signal messages from an alleged “Antifa” supporter from his iPhone. This was possible because iOS apparently temporarily stores newly incoming messages in its database if they are displayed with their full content by the operating system's notification system. The storage thus also occurs if the messages and the app – in this case, Signal – are deleted from the iPhone.
“Notifications marked for deletion could be unexpectedly retained on the device,” is Apple's sober description of the gap (CVE-2026-28950). This “logging problem” is fixed by improved data masking.
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Signal emphasized on Thursday that it was “very happy” about the patch. Users don't need to do anything other than install the update, explain the developers of the crypto messenger. All accidentally retained messages will be deleted, and no new ones will be temporarily stored.
Signal CEO Meredith Whittaker had previously stated that deleted messages should never “remain in any operating system database.” The crypto messenger had therefore contacted Apple directly. Some messengers, including Signal, offer the option to display new messages without content and sender name. This also prevents unintentional storage in operating system databases. Users of older iOS versions for which no patch is available can and should continue to use this as a workaround.
Update also for all devices with iOS 18
At least iOS 18.7.8 is also available for current iPhones. So users are not forced to upgrade to the Liquid Glass version iOS 26 for this. Apple had originally discontinued the patches for iOS 18 on current devices that can update to iOS 26 at the end of last year. The massive threat posed by powerful spyware tools in the wild then led to a rethink by the company and the renewed provision of patches for the older operating system version up to the iPhone 16 and 16e.
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