News > Phones iOS 12.5.4 Brings Security Updates to Older Apple Devices Addressing vulnerabilities from Webkit and memory corruption By Rob Rich Rob Rich Twitter News Reporter College for Creative Studies Rob is a freelance tech reporter with experience writing for a variety of outlets, including IGN, Unwinnable, 148Apps, Gamezebo, Pocket Gamer, Fanbolt, Zam, and more. lifewire's editorial guidelines Updated on June 15, 2021 01:01PM EDT Fact checked by Rich Scherr Fact checked by Rich Scherr Twitter University of Maryland Baltimore County Rich Scherr is a seasoned technology and financial journalist who spent nearly two decades as the editor of Potomac and Bay Area Tech Wire. lifewire's fact checking process Tweet Share Email Tweet Share Email Phones Mobile Phones Internet & Security Computers & Tablets Smart Life Tech Leaders Home Theater & Entertainment Software & Apps Social Media Streaming Gaming Women in Gaming Older Apple Devices have received a new security update that fixes a number of exploitable issues that would leave users open to malicious commands. According to Apple, a new update for older model Apple devices removes some code from the ASN.1 decoder, which was causing a memory corruption issue that could be exploited by "processing a maliciously crafted certificate." Apple This means that someone could use or alter a set of user credentials in order to trick the system into running other commands, like opening or downloading malicious content without the user's knowledge or consent. One of the weaknesses in Webkit is similar to the ASN.1 decoder problem with memory corruption, though instead of a decoder exploit, it was possible for malicious web content to run commands. Apple goes on to acknowledge that this particular exploit may have been actively used in the past, before the update. The second Webkit issue also allowed web content to execute commands, but was tied to a Use-After-Free vulnerability. UAF relates to the issue of accessing memory that already has been freed by having a memory pointer/address intended for one process carried over to another. This can lead to memory corruption and malicious command execution, and even enable the ability to remotely run code. Apple The iOS 12.5.4 update is available for the iPhone 5s, iPhone 6, iPhone 6 Plus, iPod Touch, iPad Mini 2, iPad Mini 3, and iPad Air and addresses security vulnerabilities from memory corruption and Webkit. Apple urges those who can download the update to do so, as it closes a few significant openings—some of which have likely been previously exploited. Was this page helpful? Thanks for letting us know! Get the Latest Tech News Delivered Every Day Subscribe Tell us why! Other Not enough details Hard to understand Submit