What does Kerberos pre-authentication failed mean?
This problem can occur when a domain controller doesn’t have a certificate installed for smart card authentication (for example, with a “Domain Controller” or “Domain Controller Authentication” template), the user’s password has expired, or the wrong password was provided.
Can Kerberos be disabled?
Disclaimer: Microsoft says that “Disabling Kerberos Pre-Authentication must not be disabled“. Without Kerberos Pre-Authentication a malicious attacker can directly send a dummy request for authentication. The KDC will return an encrypted TGT and the attacker can brute force it offline.
What is Kerberos pre-authentication?
Kerberos Pre-Authentication is a security feature which offers protection against password-guessing attacks. The AS request identifies the client to the KDC in Plaintext. If Kerberos Pre-Authentication is enabled, a Timestamp will be encrypted using the user’s password hash as an encryption key.
What is error code 0x18?
The failure code 0x18 means that the account was already disabled or locked out when the client attempted to authenticate. You need to find the same Event ID with failure code 0x24, which will identify the failed login attempts that caused the account to lock out.
What is result code 0X12?
According to my research, the code 0X12 means client’s credentials have been revoked. This might be because of an explicit disabling or because of other restrictions in place on the account. For example: account disabled, expired, or locked out.
How do I disable Kerberos authentication?
Procedure
- Log on to the host on which you want to disable Kerberos authentication.
- Edit ego. conf at EGO_CONFDIR to remove the EGO_AUTH_PLUGIN parameter. When you disable Kerberos, the message-integrity check is also disabled.
What is a pre authentication?
Pre-authentication rules determine the conditions that must be satisfied before a user is allowed to authenticate. Just because a user is able to provide a valid one-time passcode does not necessarily mean that they should be granted access to the network.
What is error code 0xc0000234?
0xc0000234 – The user account has been automatically locked because too many invalid logon attempts or password change attempts have been requested.