[Possible APG bug] Log Roller Trait using CMB instead of CMD?

[The Only Sheet]

Quote:

Log Roller (forest): The time you spent leaping between

slippery logs as they whirled down the river to market
taught you how to keep your footing. You gain a +1 trait
bonus on Acrobatics checks and a +1 trait bonus to your
CMB when attempting to resist trip attacks.

Is you are resisting a trip attack, shouldn't this trait give you a bonus on your CMD and not your CMB??

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