Apple Pulls iOS 16.5.1 and macOS 13.4.1 Rapid Security Response Updates Due to Safari Bug

Apple earlier today released new Rapid Security Response updates for iOS 16.5.1, iPadOS 16.5.1, and macOS Ventura 13.4.1 users, but Apple has pulled the software, likely due to an issue that caused certain websites not to work after the RSRs were installed.

Rapid Security Response Feature 1
According to reports on the MacRumors forums, Facebook, Instagram, WhatsApp, Zoom, and other websites started giving a warning about not being supported on the Safari browser following the Rapid Security Response updates.

The iOS 16.5.1, iPadOS 16.5.1, and macOS Ventura 13.4.1 Rapid Security Response updates fixed a WebKit vulnerability that Apple says may have been actively exploited. Unfortunately, it appears that the updates changed the Safari user agent to include an (a), leading some websites to break.

Apple will likely re-release the RSRs when the issue has been addressed.


Those who have already installed the update can downgrade on iOS by going to Settings > General > About and tapping on iOS Version. From there tap on Remove Security Update. On the Mac, updates can be removed by following our how to.

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Top Rated Comments

dumastudetto Avatar
30 months ago
I won’t be uninstalling a fix for an actively exploited security bug to workaround sloppy Meta website code.
Score: 56 Votes (Like | Disagree)
Will Co Avatar
30 months ago
Install the RSR. Stop using Facebook.
Score: 25 Votes (Like | Disagree)
airwalk331 Avatar
30 months ago
Final_update_16.5.1.ax_finalv2_final_fix.dmg
Score: 23 Votes (Like | Disagree)
ZZ9pluralZalpha Avatar
30 months ago

Zoom is in fact affected by the same issue (which, again, is Zoom's fault).
Not comforting that so many apps have user agent parsers which will fall flat on their faces when presented with an '(a)'...
Score: 22 Votes (Like | Disagree)
krspkbl Avatar
30 months ago
Breaks Facebook and Instagram? Sounds like a feature to me!
Score: 18 Votes (Like | Disagree)
ChedNasad Avatar
30 months ago
And here I thought Zuck was just fed up with Apple's anti tracking policies...
Score: 17 Votes (Like | Disagree)