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Whether you have a MacBook Neo or an iMac, stay vigilant: Hackers are exploiting a known security vulnerability in macOS that allows bad actors to activate Screen Sharing without the proper permissions. Because macOS lets screen sharers control screens remotely, this flaw is particularly dangerous. Luckily, Apple fixed this issue before anyone knew the flaw was exploited.

The company released three new security updates for Macs on Thursday, Aug. 6. You don't need to be running the latest version, macOS 26, to take advantage of these updates, either. While the company does have a new Tahoe update, Apple's security updates here include releases for both macOS 15 Sequoia and macOS 14 Sonoma as well—and all of these updates patch this screen sharing flaw.

macOS Tahoe 26.6.1, macOS Sequoia 15.7.9, and macOS Sonoma 14.8.9 all contain the same, singular security patch: Tracked as CVE-2026-65400, this fix is for a Screen Sharing flaw that Apple says could allow an attacker on your network to "authenticate to Screen Sharing without valid credentials." In layman's terms, this security flaw could let hackers activate Screen Sharing without permission, which would leave the contents of your Mac's display totally open to anyone in the know.

Apple's Screen Sharing feature is complex, which is good for usability but potentially dangerous in this case. Not only can people using Screen Sharing see your Mac's display, they can, if prompted, take over your Mac as well. Typically, this requires permissions on both sides to activate, so a bad actor could also theoretically take control of your computer using this flaw—accessing your files, messages, or anything else on your Mac.

At the time, Apple did not say that this flaw was previously publicly disclosed or being actively exploited, so it's not clear how long hackers have been using it. But it's likely we'll see more cases like this going forward: Certain AI models, like Claude Mythos, are adept at discovering security vulnerabilities, so it's possible someone out there could have found this flaw before Apple did. Luckily, the patch is now out for anyone running the latest three versions of macOS, so all you have to do to protect yourself is update your Mac.

Whether your Mac is brand new or a few versions behind, there's a very good chance you can install one of these security patches. To do so, open System Settings > General > Software Update, let macOS look for the update, then follow the on-screen instructions to download and install it.