What if you have 10 of the 12 words in their proper order so you just need the last 2 words in the correct order?
With 10 out of 12 words you reduce the possible (theoretical amount of) combinations to 2048
2 =
4.194.304Checking this amount is definetely possible in a short amount of time.
Considering that the last word 'contains' a checksum, the actual amount of combinations is lower than 4.194.304, making it even easier to bruteforce them.
With 10 words exposed you should definetely regard your seed as compromised and switch as soon as possible.