Apple has patched a security flaw that could be used by hackers to install undetectable malware.

Researchers at Microsoft discovered the vulnerability, which could be used to install a rootkit, residing within the macOS System Integrity Protection (SIP). The vulnerability allowed hackers to overwrite system files and install undetectable malware. Jonathan Bar Or, a Microsoft researcher, posted the findings on the Microsoft 365 Defender Research Team blog. Ironically, the SIP within macOS is technology that restricts users from undertaking operations that could compromise security; the flaw within the SIP is how hackers were able to get in.

The security flaw, named CVE-2021-30892, was patched in macOS Monterey 12.0.1, with an update also available for users running Catalina and Big Sur. This security flaw is the latest in an increasingly long line of vulnerabilities targeting Macs users, as more and more people switch from Windows. The old wisdom – that Macs don’t get viruses or malware and that you don’t need to be on the lookout for threats – is outdated. Mac viruses are out there, and Mac users need to ensure that they are following best practices, such as having a decent antivirus and ensuring that all the latest security updates are installed.