ICU1021 WEAK SYSTEM MASTER KEY SPECIFIED

Explanation
A weak value for the new host master key was specified
in the PARM field of the EXEC statement for the key generator utility
program.

System action
Key generator utility processing ends.

Programmer response
Supply a new host master key value and its
complement in the PARM field of the EXEC statement. See z/OS DFSMS Using Data Sets for
a description of weak key values. Rerun the key generator utility
program.
To ensure that you have all the
messages issued for this problem, specify MSGLEVEL=(1,1) for the job.

Source
Cryptographic Unit Support Program (CUSP)