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Security Update 2021-002 Catalina and 2021-003 Mojave

Apple has released Security Update 2021-002 for macOS 10.15 Catalina and Security Update 2021-003 for 10.14 Mojave, patching 31 security vulnerabilities in Catalina and 30 vulnerabilities in Mojave. Both updates address memory corruption and handling issues with the kernel that could elevate privileges or allow kernel memory disclosure, a Wi-Fi-related memory corruption issue that could allow an app to cause unexpected system termination or write kernel memory, and a Windows Server issue that could leak a user’s credentials from secure text fields. Although many people have updated without problems, it appears that Security Update 2021-002 for Catalina breaks OpenCL, which can break graphics apps—Flying Meat’s Acorn 6 and Retrobatch are negatively impacted. We recommend holding off on these updates until more is known. If you notice any other problems after updating, please let us know in the comments. (Free, various sizes, Catalina release notes and Mojave release notes, macOS 10.15.7 and 10.14.6)

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Comments About Security Update 2021-002 Catalina and 2021-003 Mojave

Notable Replies

  1. Installed…Mojave system…zero issues

  2. Catalina version worked for me

  3. Installed Catalina update. So far the only issue is that it had the fan on my MacBook Pro running full bore, and the keyboard was hot. I actually used a thin book to prop up the front of the MacBook Pro to let air around the unit. :woman_shrugging:

  4. My Catalina and Mojave drives did not report any security updates to install.

  5. This update of Catalina resulted in Safari 14.1 having issues with constant reloading of financial websites (like and banking sites). It is probably a problem with Java, since disabling Java loads the website just fine, but login is not possible. I’ve notified Apple, but customer support advisor was of no help. Safari is basically unusable and I’ve switched to Chrome. Would advise DO NOT update until Apple addresses this issue with Safari.

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