Following its recent release, Apple’s latest macOS update, dubbed Sequoia (macOS 15), has disrupted the functionality of several widely used cybersecurity tools, including those from CrowdStrike, SentinelOne, and Microsoft. 

Users and developers have voiced frustrations on social media and in Mac-focused forums about issues leaving many security applications non-operational. Reports highlight problems with tools like CrowdStrike, SentinelOne, Microsoft Defender, and ESET, alongside browser issues, particularly with Firefox, where the OS firewall sometimes blocks web access. The root cause is unclear, but the disruptions are creating significant challenges for both end-users and enterprise security teams. 

The key issue seems to stem from changes Apple has made in Sequoia’s network stack, which cybersecurity firms say is interfering with their products. For example, CrowdStrike delayed support for Sequoia, citing complications in adapting their software. Similarly, SentinelOne warned users not to upgrade without ensuring proper support, while Microsoft’s Defender and ESET have faced similar difficulties. Despite SentinelOne and ESET eventually providing compatibility, significant disruption remains across the community. 

Apple has yet to comment, leaving security firms and users to manage the situation. CrowdStrike is awaiting a Sequoia update to offer full support, while temporary workarounds are being shared to address issues like firewall settings and basic web browsing. For now, it may be advisable to delay upgrading to macOS Sequoia until Apple or security providers release compatible updates.