After a system upgrade, when running tools such as Metasploit, GVM, or Bloodhound, you may encounter PostgreSQL error messages. These errors prevent the tools from functioning properly, citing “collation version mismatch” errors such as the following:

WARNING:  database "postgres" has a collation version mismatch
DETAIL:  The database was created using collation version 2.40, but the operating system provides version 2.41.
HINT:  Rebuild all objects in this database that use the default collation and run ALTER DATABASE postgres REFRESH COLLATION VERSION, or build PostgreSQL with the right library version.

This errors can be fixed by running the following command in Kali’s terminal:

┌──(kali㉿kali)-[~]
└─$ sudo runuser -u postgres -- psql -c 'ALTER DATABASE postgres REFRESH COLLATION VERSION; ALTER DATABASE template1 REFRESH COLLATION VERSION;'