A method for identifying a corrupted received signal that includes symbols is described. Each symbol may have a value of a Galois field associated therewith. The receiver may be configured to store a logarithm of normalized probability mass functions and corresponding Galois field values for each of the symbols. The normalized probability mass functions may be normalized with respect to a greatest probability mass function of a given symbol. The method may include comparing, for each symbol, a logarithm of normalized probability of an n-th best probability value with a respective threshold, counting a number of the logarithms that exceed the respective threshold and generating, for each symbol, a score corresponding to the number. The method may also include calculating a moving average of the scores, and comparing the moving average with an output threshold and flagging a just received symbol as corrupted based upon the comparison.