diff --git a/lib/rex/proto/kerberos/model.rb b/lib/rex/proto/kerberos/model.rb
index bbdbb57eef..f0c2261793 100644
--- a/lib/rex/proto/kerberos/model.rb
+++ b/lib/rex/proto/kerberos/model.rb
@@ -17,6 +17,57 @@ module Rex
         AUTHENTICATOR = 2
         AP_REQ = 14
 
+        # Kerberos error codes
+        ERROR_CODES = {
+          0 => ['KDC_ERR_NONE', 'No error'],
+          1 => ['KDC_ERR_NAME_EXP', 'Client\'s entry in database has expired'],
+          2 => ['KDC_ERR_SERVICE_EXP', 'Server\'s entry in database has expired'],
+          3 => ['KDC_ERR_BAD_PVNO', 'Requested protocol version number not supported'],
+          4 => ['KDC_ERR_C_OLD_MAST_KVNO', 'Client\'s key encrypted in old master key'],
+          5 => ['KDC_ERR_S_OLD_MAST_KVNO', 'Server\'s key encrypted in old master key'],
+          6 => ['KDC_ERR_C_PRINCIPAL_UNKNOWN', 'Client not found in Kerberos database'],
+          7 => ['KDC_ERR_S_PRINCIPAL_UNKNOWN', 'Server not found in Kerberos database'],
+          8 => ['KDC_ERR_PRINCIPAL_NOT_UNIQUE', 'Multiple principal entries in database'],
+          9 => ['KDC_ERR_NULL_KEY', 'The client or server has a null key'],
+          10 => ['KDC_ERR_CANNOT_POSTDATE', 'Ticket not eligible for postdating'],
+          11 => ['KDC_ERR_NEVER_VALID', 'Requested start time is later than end time'],
+          12 => ['KDC_ERR_POLICY', 'KDC policy rejects request'],
+          13 => ['KDC_ERR_BADOPTION', 'KDC cannot accommodate requested option'],
+          14 => ['KDC_ERR_ETYPE_NOSUPP', 'KDC has no support for encryption type'],
+          15 => ['KDC_ERR_SUMTYPE_NOSUPP', 'KDC has no support for checksum type'],
+          16 => ['KDC_ERR_PADATA_TYPE_NOSUPP', 'KDC has no support for padata type'],
+          17 => ['KDC_ERR_TRTYPE_NOSUPP', 'KDC has no support for transited type'],
+          18 => ['KDC_ERR_CLIENT_REVOKED', 'Clients credentials have been revoked'],
+          19 => ['KDC_ERR_SERVICE_REVOKED', 'Credentials for server have been revoked'],
+          20 => ['KDC_ERR_TGT_REVOKED', 'TGT has been revoked'],
+          21 => ['KDC_ERR_CLIENT_NOTYET', 'Client not yet valid - try again later'],
+          22 => ['KDC_ERR_SERVICE_NOTYET', 'Server not yet valid - try again later'],
+          23 => ['KDC_ERR_KEY_EXPIRED', 'Password has expired - change password to reset'],
+          24 => ['KDC_ERR_PREAUTH_FAILED', 'Pre-authentication information was invalid'],
+          25 => ['KDC_ERR_PREAUTH_REQUIRED', 'Additional pre-authentication required'],
+          31 => ['KRB_AP_ERR_BAD_INTEGRITY', 'Integrity check on decrypted field failed'],
+          32 => ['KRB_AP_ERR_TKT_EXPIRED', 'Ticket expired'],
+          33 => ['KRB_AP_ERR_TKT_NYV', 'Ticket not yet valid'],
+          34 => ['KRB_AP_ERR_REPEAT', 'Request is a replay'],
+          35 => ['KRB_AP_ERR_NOT_US', 'The ticket isn\'t for us'],
+          36 => ['KRB_AP_ERR_BADMATCH', 'Ticket and authenticator don\'t match'],
+          37 => ['KRB_AP_ERR_SKEW', 'Clock skew too great'],
+          38 => ['KRB_AP_ERR_BADADDR', 'Incorrect net address'],
+          39 => ['KRB_AP_ERR_BADVERSION', 'Protocol version mismatch'],
+          40 => ['KRB_AP_ERR_MSG_TYPE', 'Invalid msg type'],
+          41 => ['KRB_AP_ERR_MODIFIED', 'Message stream modified'],
+          42 => ['KRB_AP_ERR_BADORDER', 'Message out of order'],
+          44 => ['KRB_AP_ERR_BADKEYVER', 'Specified version of key is not available'],
+          45 => ['KRB_AP_ERR_NOKEY', 'Service key not available'],
+          46 => ['KRB_AP_ERR_MUT_FAIL', 'Mutual authentication failed'],
+          47 => ['KRB_AP_ERR_BADDIRECTION', 'Incorrect message direction'],
+          48 => ['KRB_AP_ERR_METHOD', 'Alternative authentication method required'],
+          49 => ['KRB_AP_ERR_BADSEQ', 'Incorrect sequence number in message'],
+          50 => ['KRB_AP_ERR_INAPP_CKSUM', 'Inappropriate type of checksum in message'],
+          60 => ['KRB_ERR_GENERIC', 'Generic error'],
+          61 => ['KRB_ERR_FIELD_TOOLONG', 'Field is too long for this implementation']
+        }
+
         KDC_OPTION_RESERVED        = 0
         KDC_OPTION_FORWARDABLE     = 1
         KDC_OPTION_FORWARDED       = 2
diff --git a/modules/auxiliary/admin/kerberos/ms14_068_kerberos_checksum.rb b/modules/auxiliary/admin/kerberos/ms14_068_kerberos_checksum.rb
index 5e5dc2344f..486b89cc5e 100644
--- a/modules/auxiliary/admin/kerberos/ms14_068_kerberos_checksum.rb
+++ b/modules/auxiliary/admin/kerberos/ms14_068_kerberos_checksum.rb
@@ -84,6 +84,7 @@ class Metasploit4 < Msf::Auxiliary
     )
 
     unless res.msg_type == Rex::Proto::Kerberos::Model::AS_REP
+      vprint_warning("#{peer} - #{warn_error(res)}") if res.msg_type == Rex::Proto::Kerberos::Model::KRB_ERROR
       print_error("#{peer} - Invalid AS-REP, aborting...")
       return
     end
@@ -132,6 +133,7 @@ class Metasploit4 < Msf::Auxiliary
     )
 
     unless res.msg_type == Rex::Proto::Kerberos::Model::TGS_REP
+      vprint_warning("#{peer} - #{warn_error(res)}") if res.msg_type == Rex::Proto::Kerberos::Model::KRB_ERROR
       print_error("#{peer} - Invalid TGS-REP, aborting...")
       return
     end
@@ -143,5 +145,18 @@ class Metasploit4 < Msf::Auxiliary
     path = store_loot('windows.kerberos', 'application/octet-stream', rhost, cache.encode)
     print_good("#{peer} - MIT Credential Cache saved on #{path}")
   end
+
+  def warn_error(res)
+    msg = ''
+
+    if Rex::Proto::Kerberos::Model::ERROR_CODES.has_key?(res.error_code)
+      error_info = Rex::Proto::Kerberos::Model::ERROR_CODES[res.error_code]
+      msg = "#{error_info[0]} - #{error_info[1]}"
+    else
+      msg = 'Unknown error'
+    end
+
+    msg
+  end
 end