Dan Pražák Apple released iOS 12.4.1, watchOS 5.3.1 and tvOS 12.4.1 this evening. A revised version of macOS 10.14.6 was also released along with them. New updates are available for regular users and bring security bug fixes.
Owners of compatible devices can download new secondary versions of systems in Settings on iPhone, iPad and Apple TV, v the Watch app on iPhone and System preferences on a Mac. These are only minor updates, which is also reflected in the size of the installation packages. Apple basically just eliminated the vulnerabilities and improved the overall stability of the systems.
In the case of iOS 12.4.1, the company then managed to fix a security flaw that allowed iPhones and iPads with iOS 12.4 to be jailbroken. Apple already released a patch for the same bug in iOS 12.3, but subsequently inadvertently revealed it again with the release of the next update, allowing the relevant community to create a jailbreak for the system. So if for any reason you have a jailbroken device, or plan to do so, then don't update.
