linux – SQL Server 2019 on Ubuntu Throwing security.crypto.symkey errors

I’m repeatedly seeing the following error, seemingly for every connection to SQL:

04/06/2021 16:39:25.890647613 Error [security.crypto.symkey] <0000004241/0x00000c34> Setting Variable Length cipher failed
04/06/2021 16:39:25.891039957 Error [security.crypto.symkey] <0000004246/0x00000c48> Setting Variable Length cipher failed
04/06/2021 16:39:25.891219869 Error [security.crypto.symkey] <0000003401/0x0000022c> Setting Variable Length cipher failed
04/06/2021 16:39:25.891406611 Error [security.crypto.symkey] <0000006256/0x00000d84> Setting Variable Length cipher failed
04/06/2021 16:39:25.891603673 Error [security.crypto.symkey] <0000003402/0x00000230> Setting Variable Length cipher failed
04/06/2021 16:39:25.891801766 Error [security.crypto.symkey] <0000005939/0x00000d74> Setting Variable Length cipher failed
04/06/2021 16:39:25.891984227 Error [security.crypto.symkey] <0000004242/0x00000c38> Setting Variable Length cipher failed
04/06/2021 16:39:25.892166190 Error [security.crypto.symkey] <0000003501/0x000003ac> Setting Variable Length cipher failed

Pertinent logger.ini file configuration:

[Output:Security]
Type = File
Filename = /var/opt/mssql/log/security.log
Maxfilesizemb = 1000
Maxrolloverfiles = 8

...

[Logger.security]
Level = Info
Outputs = Security

SQL authenticates against AD using a kerberos keytab file:

[network]
privilegedadaccount = xxxxx
kerberoskeytabfile = /var/opt/mssql/xxxxx/mssql.keytab
tlscert = /etc/xxxxx/mssql.pem
tlskey = /etc/xxxxx/mssql.key
tlsprotocols = 1.2
forceencryption = 1
tlsciphers = AES256-GCM-SHA384:AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256 ...

Any ideas what might be causing the error or where else I should be looking? It doesn’t seem to be impacting things besides generating a large number of errors in the log.