Users can upgrade to iOS 13.2.2.
On November 8th, Apple released iOS 13.2.2 to all users, fixing many bugs (including the issue that caused background apps to unexpectedly quit). A week later, iOS 13.2 code signing was stopped, and users who had already upgraded could no longer download iOS 13.2 from Apple's servers.
iOS 13.2.2 includes bug fixes and improvements for iPhone:
• Fixes an issue that could cause background-running apps to unexpectedly quit
• Resolves an issue where iPhone may temporarily lose cellular service after a call ends
• Fixes an issue where cellular data may temporarily not be available
• Fixes an issue that prevented reading replies to S/MIME encrypted emails between Exchange accounts
• Resolves an issue where Safari may prompt for authentication when using Kerberos single sign-on services
• Fixes an issue where YubiKey accessories powered by Lightning may experience charging interruptions
Apple's timely closure of the iOS 13.2 downgrade is due to the numerous system issues present in this official version. Additionally, the well-known "checkm8" vulnerability has attracted attention as it provides the possibility of jailbreaking iPhones, including the iPhone X.
Earlier this week, Apple released the second beta of iOS 13.3, which includes some minor adjustments and fixes to the system. The most notable update is the support for NFC, USB, and Lightning security keys in Safari.