Signal / WhatsApp "good news"
The fact that they rely on compromising the phone to get at Signal / WhatsApp should not be read to imply those are secure. More that compromising the phone is so easy with the menu of exploits at their disposal that give them access more than just Signal / WhatsApp that there's no point in compromising just one app at a time even if they can.
Also, the NSA are the codebreakers that would attack those apps via a weakness in their protocol, not the CIA. If the NSA found such a weakness, they'd use it to hoover up communication from many users, not just a few targeted ones. And they likely wouldn't tell the CIA they had such a capability, the intelligence world is rife with turf wars, despite the attempt via the creation of the department of homeland security to get them all playing nice with each other.