Apple is urging iPhone users to upgrade their devices after millions failed to install key security updates released more than six weeks ago.
The company issued security fixes in mid-December but required users to upgrade to iOS 26 to receive them. Devices still running iOS 18 have remained vulnerable during this period.
Security analysts warn the issue involves flaws in Apple’s WebKit software, which powers web browsing on iPhones. These flaws were first linked to targeted attacks but are now considered a broader risk.
Experts estimate that hundreds of millions of iPhones may still be affected. While exact numbers are unclear, analysts say the scale is large enough to raise serious concerns.
Apple also delayed a smaller update that would have forced affected devices to restart. Many users rarely reboot their phones, which further increases exposure to active threats.
Beyond WebKit, iOS 26.2 includes more than 25 security fixes. Apple has not confirmed whether any of these vulnerabilities are now being exploited.
Apple is expected to release iOS 26.3 soon, with additional security updates and system improvements. However, experts say users should not wait for the next version.
Security specialists advise iPhone users to upgrade to iOS 26 immediately. Updating now applies all fixes and restarts the device, restoring its intended level of protection.
