When connecting to Server 5.6: password hash should be a 41-digit hexadecimal number (code 1372) (no replies)

Hi - I'm running Workbench 8.0.17, and when connecting to a MySQL 5.6 server as a user with an expired password, I get prompted to change my password ("Password for MySQL account blah expired. Please pick a new password.") I enter my old password and a new password, click OK, and then I get "Password hash should be a 41-digit hexadecimal number (code 1372).

Only seems to happen when connecting to 5.6; connections to 5.7 are fine. And if I connect to the same 5.6 server with the same account using the MySQL CLI, it works fine:

rowagn@dig229au:~#> /sso/sfw/mysql/bin/mysql -utest -ptest -hblah.com
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1016592
Server version: 5.6.10

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Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use information_schema
ERROR 1820 (HY000): You must SET PASSWORD before executing this statement
mysql> set password = password('test123');
Query OK, 0 rows affected (0.01 sec)

I suspect Workbench is sending "set password = 'secretPassword'" instead of "set password = password('secretPassword')".

Any way to resolve this? Thanks.