Is there any guideline or consensus about reviewer's scores from ACM? I have been wondering about if there is any document in which is stated the criteria for scoring an article according to ACM. For example, for the ACM Symposium on Applied Computing I thought that the scores were from 1 to 5, but I have seen some parts that they put a 6, or maybe is a typo?
Does anyone knows the ACM criteria or the ranges of those scores?
There is no such thing as “scoring an article according to ACM”.

I have seen scoring systems that rate papers on a scale from 0 to 3, from 0 to 10, from -5 to 5, from 0 to 6, from 1 to 7, ....  Scoring rules vary significantly from one conference to the next, sometimes even from one iteration to the next of the same conference.  These rules are decided by the program committee chair, sometimes but not always in consultation with the other members of the program committee and/or the conference steering committee.

Moreover, even when conferences use the same numerical scale, the meanings of the numbers change from one conference to the next.  For example, on a scale from 1 to 10, a score of 7 might mean "weak accept" (leaving 8–10 for "accept", "strong accept", and "best paper"), or it might mean "strong accept" (leaving 8-10 for "plenary session", "best paper", and "Turing award").

The publisher (in this case ACM) plays absolutely no role in the design of these scales.