CAN bus cable-termination mismatch
That’s not that bad a mismatch. Unless you are already at an extremely marginal situation, it shouldn’t have any impact. 

To see that via theory, when the bit wave reaches a terminator, I and V are balanced around 100 ohms, a 1:100 ratio. Suddenly the terminator is forcing a 1:120 ratio and that mismatch will cause reflections of the wave. That’s a mismatch by about 1/6th, so if you’ve got 30% margin you’re still good. 

Empirically, if you do have a problem you can add 600 ohm resistors to the two (and only two!) existing terminators  to make them effectively 100ohms.