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On Monday, Apple released its latest iteration of Mac’s operating system, macOS Sequoia. The new update introduced tighter control over app permissions and an overhaul to Gatekeeper, among other features. However, according to TechCrunch, it now appears to be disrupting security tools made by CrowdStrike, SentinelOne, and Microsoft. Social media users are also reporting connection failures with third-party VPNs.

Details are sparse at the moment, but a possible source of the issues is Sequoia’s current firewall. This is useful for managing connections on untrusted networks. If you’re an everyday user and not a security nut or part of an enterprise team, your firewall is likely already off. This is the default on Mac, as most users are on trusted networks anyway (Apple’s way of balancing usability and security).

Many experts have noticed that turning off the firewall fixes the disruptions to any network-based tools. However, if the firewall is already enabled to begin with, you probably wouldn’t want to do this.

Patrick Wardle, a long-time iOS and Mac security expert and founder of the Objective-See Foundation, expressed his frustration, noting that Apple’s lack of thorough testing is to blame.

“Déjà vu?! Did Apple *again* release a new OS that *again* breaks 3rd-party security tools?” Wardle posted on his LinkedIn in reference to a bug two years ago in MacOS Ventura that caused similar problems. “Root cause appears to either be macOS firewall itself, or the lower-level networking extension subsystem that is “corrupting packets” or other “unintentional changes” to network structures,” he added.

Other security-focused communities are sharing similar concerns. Vulnerability researcher Will Dormann shared in a blog post that DNS requests over a network are blocked by macOS Sequoia when the firewall is set to “Block incoming connections,” which unexpectedly includes DNS responses. This issue did not exist in previous macOS versions, and it seems to be a bug in the current firewall. “Any response to a request that I initiate should be allowed in.”

Dormann also noted that another problem is that Sequoia’s firewall GUI is not synced correctly with the actual firewall rules, making it difficult for users to adjust or modify settings, especially for those using older Macs.

This would undoubtedly cause issues connecting to third-party VPNs. I’m currently having issues connecting with Windscribe on macOS Sequoia. Other members of 9to5Mac have no problems with Nord VPN. What about you?

If you’re a user of Crowdstrike, it appears Apple has already confirmed the networking issues happening. Hopefully a fix in the works 🤞 and coming soon.