This bifunctional enzyme catalyzes two consecutive reactions during ribonucleic acid degradation. Converts a 2',3'-cyclic nucleotide to a 3'-nucleotide and then the 3'-nucleotide to the corresponding nucleoside and phosphate. a nucleoside 2',3'-cyclic phosphate + H2O = a nucleoside 3'-phosphate + H(+) a ribonucleoside 3'-phosphate + H2O = a ribonucleoside + phosphate Two kinetically distinguishable active sites for the two substrates (2',3'-cyclic nucleotides and 3'-nucleotides) have been identified. Belongs to the 5'-nucleotidase family.