There is no hard cut-off, however, MBB firms prefer candidates with min. 3.70 GPA from target schools. If you fall below this, this does not mean that you won't get an interview invite, however you need to highlight your other strengths on your CV e.g. relevant job experience.
There is no cutoff and your application is considered as a whole. Some offices may have automated the process but for sure a lot of work is still done manually. Thus make sure that you have the keywords in your resume (universities, brands, etc). The most important is - the ranges for these criteria are not set in stone. There may be a lot of factors influencing the cut-offs:
...and many others. You should do your best (Resume, CL, get a referal, smartly select the preferable offices) and keep your fingers crossed.
Agreed there is not an automatic cutoff, but low GPA doesn't help - the more "distanced" you are from it the less impact it will have (to Vlad's point, it is still looked at).
In my opinion, there's no harm in trying, but make sure you really highlight your other achievements.
Additionally, acquiring additional work experience and getting an MBA does increase your chances (not to mention, reduces focus on undergrad GPA). Also, getting an MBA generally puts you in the situation of being able to apply for a Consultant role over an Associate role, which is certainly a big jump.
It doesn't mean that you will be cut off. It means that you can highlight your achievements in you CV and polish you cover letter, and also increase your chances with referral.
If you need any further help with resume or referral, feel free to reach me out.