""GPL SMTP AUTH LOGON brute force attempt""
SID: 2102275
Revision: 3
Class Type: suspicious-login
Metadata: created_at 2010_09_23, updated_at 2012_01_16
Reference:
Protocol: tcp
Source Network: $SMTP_SERVERS
Source Port: 25
Destination Network: $EXTERNAL_NET
Destination Port: any
Flow: from_server,established
Contents:
- Value: "Authentication unsuccessful"
Offset: 54
Within:
PCRE:
Special Options:
- nocase