Apple rushes out emergency fix for screen sharing flaw on Macs - update ASAP

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Apple has pushed out new updates for MacOS Tahoe, Sonoma, and Sequoia in light of a serious security vulnerability.

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Released on Thursday, the updates for all three systems patch a flaw that could allow an attacker to exploit the Screen Sharing feature to access and control your Mac.

The updates are available in three different versions, depending on which OS you run -- MacOS Tahoe 26.6.1 , MacOS Sonoma 14.8.9 , and MacOS Sequoia 15.7.9 .

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To install the update, head to System Settings, select General, and then click Software Update. Allow the update to appear, and then click the Update Now button to install it.

Since these updates were unexpected, Apple must have considered the flaw serious enough to warrant an immediate fix. And that certainly seems to be the case. The description on the support pages says that an attacker may be able to authenticate to Screen Sharing without valid credentials.

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The ability to remotely connect to another Mac has long been built into MacOS. But the current iteration of the Screen Sharing app was introduced in 2023 with MacOS Sonoma . Using this tool, you're able to access and control another Mac on your network. But to do this, you must supply a valid username and password.

Based on the description of the vulnerability, an attacker could bypass the normally required authentication and gain control of your Mac without your permission or authorization. From there, they could easily view your personal files, tamper with Mac features and settings, install malware, and even enlist your system in a botnet from which to target other computers.

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For such an attack to succeed on a home or protected network, the hacker would first need to gain that initial access. But on a public and unprotected network, that access would be easy enough to pull off.

Apple didn't indicate that the flaw had been exploited in any known attacks. But the potential is there, which is why you should install the update ASAP.