The full name of this algorithm is 'Commercial Data Masking Facility'.

CDMF is a weaker version of DES-CBC which uses only 40 bits for encryption, and was used historically to accommodate U.S. government restrictions on the export of DES-based cryptography; these restrictions are no longer in force today.

Since DES is a stronger cryptographic algorithm, it should generally be used in preference to CDMF if security is a concern.