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Microsoft patch(CVE-2022-37966) forcing AES for Kerberos authentication - CIFS outage

Last Updated:

Applies to

  • 7-Mode
  • CIFS
  • Microsoft Server
  • CVE-2022-37966


  • Cannot connect to CIFS shares through hostname.
  • Cannot acquire new Kerberos tickets from the KDC.
  • In order to diagnose the issue, you will need to enable the trace options listed below.
  • These EMS messages will spam console and EMS after turning cifs.trace_login and cifs.trace_dc_connection options on:
> options cifs.trace_dc_connection on
> options cifs.trace_login on
Sat Nov 12 21:38:15 CST [cluster: Auth00: cifs.trace.GSSinfo:info]: AUTH: notice- Could not authenticate user.

Sat Nov 12 21:38:15 CST [cluster: Auth00: cifs.trace.GSSinfo:info]: AUTH: notice- Program lacks support for encryption type.

Sat Nov 12 21:38:15 CST [cluster: Auth00: auth.trace.authenticateUser.krbReject:info]: AUTH: Login attempt from <IP> rejected by Kerberos.





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