Although the issue was known to be routed in banner notifications when it was discovered, thus opening a wide range of apps that could be hit by the malicious text, today's news confirms that third-party apps can successfully transfer the bug. In Twitter, any direct message or public mention that includes the string of characters will cause a recipient's phone, with notifications turned on for Twitter, to crash immediately. A similar situation occurs when sending text chat via the Snapchat app, permanently crashing an iPhone when the user goes to read the message.
As noted in the original story, and just last night confirmed by Apple, a temporary fix for the bug remains in place in which a user can use Siri to reply to the malicious message thread in order to prevent Messages from crashing every time it is opened. The company promises that they "will make a fix available in a software update," but a time frame for any such fix wasn't given. Given that third-party apps are now becoming affected without as clear of an easy fix, Apple will probably try to put that update out as soon as possible before more permanent damage befalls any users.