IPCMSes make it somewhat easy to MitM SMS. If your system poops a cookie in the wrong place it doesn't matter if the secret is in someone's head or if it's in a hardware dongle, like you say... the hacker is "in".
My recommendation for bad guys is to not attack the part of the system where it is strong. Just sniff around a bit until you find the weak part and attack that.
Also remember most devs couldn't use a static analysis tool to save their lives (which is why mythos is relevant.) I suspect that a 15 year old copy of Fortify or CoVerity could find bugs mythos missed.
And if that doesn't work, just start scanning github repos for entropy. That's where the credentials that were accidentally published live.