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Apple patched critical flaws in macOS Monterey but not in Big Sur nor Catalina

Apple last week patched two actively exploited vulnerabilities in macOS Monterey yet has left users of older supported versions of its desktop operating system unprotected.

In a blog post on Tuesday, security biz Intego said fixes applied to address CVE-2022-22675 (AppleAVD bug) and CVE-2022-22674 (Intel Graphics Driver bug) in macOS Monterey were not backported to macOS Big Sur or macOS Catalina.

The AppleAVD issue is unpatched for macOS Big Sur, said Joshua Long, chief security analyst for Intego, while Catalina isn’t affected because it lacks the AppleAVD component for decoding audio and video. The Intel Graphics Driver flaw, he said, looks like it affects both Big Sur and Catalina.

This is the first time since the release of macOS Monterey that Apple has neglected to patch actively exploited vulnerabilities for Big Sur and Catalina

“This is the first time since the release of macOS Monterey that Apple has neglected to patch actively exploited vulnerabilities for Big Sur and Catalina,” said Long. “The previous three actively exploited vulnerabilities were each patched simultaneously for Monterey, Big Sur, and Catalina.”

Apple did not respond to a request to explain why it has left older macOS installations without updates for these particular issues.

Apple’s macOS Monterey debuted on October 25, 2021, and is the most recent macOS release. macOS Big Sur was released on November 12, 2020, and was last updated March 14, 2022. Its predecessor, macOS Catalina was released October 7, 2019, and also saw its most recent update on March 14, 2022.

Unlike Microsoft, which publishes its Windows Lifecycle Policy, Apple details hardware obsolescence dates but offers no written commitment covering its macOS support policy. In recent times, the iBiz has supported its active macOS release for a year while also publishing updates and security patches for its previous two macOS releases.

Support for macOS Catalina is expected to end around November 2022, and macOS Big Sur’s retirement date looks to be, more or less, November 2023.

According to Long, 35-40 per cent of Macs currently in use are vulnerable to one or both of these bugs.

Apple emits macOS, iOS, iPadOS patches for ‘exploited’ security bugs


Long says that security researcher Mickey Jin has confirmed that M1-based Macs running macOS Big Sur are vulnerable to the AppleAVD bug (CVE-2022-22675), as are devices running iOS 14 and iPadOS 14, which Apple stopped supporting in January.

CVE-2022-22675 is an out-of-bounds write bug and could allow arbitrary code execution with kernel privileges.

As for the Intel Graphics bug (CVE-2022-22674), Long says Intego is working to confirm Big Sur and Catalina are affected, but said that’s been difficult to establish because the out-of-bounds read vulnerability – which could allow reading kernel memory – was reported by an anonymous researcher.

But he said, “we have high confidence that CVE-2022-22674 likely affects both macOS Big Sur and macOS Catalina,” because nearly every vulnerability in the Intel Graphics Driver component in recent years has affected all versions of macOS.

Long added that there are dozens of other vulnerabilities in Big Sur and Catalina that are not being actively exploited.

“Apple has an unfortunate history of knowingly leaving ‘supported’ macOS versions unprotected from some in-the-wild, actively exploited attacks,” he said. “This type of scenario where a vendor chooses not to release a patch is sometimes referred to as a ‘perpetual zero-day.'” ®