До момента появления лога security в asterisk 10 fail2ban не мог корректно защищать asterisk от популярного вида атак — подбора sip пароля к экстеншенам.

Если у вас Asterisk 10 и новее его успешно можно использовать на пару с fail2ban. Настройка довольно простая.

1. Добавьте к /etc/asterisk/logger.conf

[general] dateformat=%F %T

и в секции [logfiles]

security => security

2. Добавьте в конец /etc/fail2ban/jail.conf

[asterisk-iptables] enabled  = true filter   = asterisk action   = iptables-allports[name=ASTERISK, protocol=all]            sendmail-whois[name=ASTERISK, dest=root, sender=fail2ban@example.org] logpath  = /var/log/asterisk/security maxretry = 5 bantime = 259200 

3. Создайте файл /etc/fail2ban/filter.d/asterisk.conf с содержимым:

# Fail2Ban configuration file # # # $Revision: 250 $ #  [INCLUDES]  # Read common prefixes. If any customizations available -- read them from # common.local #before = common.conf   [Definition]  #_daemon = asterisk  # Option:  failregex # Notes.:  regex to match the password failures messages in the logfile. The #          host must be matched by a group named "host". The tag "" can #          be used for standard IP/hostname matching and is only an alias for #          (?:::f{4,6}:)?(?P\S+) # Values:  TEXT #  failregex = SECURITY.* SecurityEvent="FailedACL".*RemoteAddress=".+?/.+?//.+?".*             SECURITY.* SecurityEvent="InvalidAccountID".*RemoteAddress=".+?/.+?//.+?".*             SECURITY.* SecurityEvent="ChallengeResponseFailed".*RemoteAddress=".+?/.+?//.+?".*             SECURITY.* SecurityEvent="InvalidPassword".*RemoteAddress=".+?/.+?//.+?".*  # Option:  ignoreregex # Notes.:  regex to ignore. If this regex matches, the line is ignored. # Values:  TEXT # ignoreregex =

Готово! fail2ban будет обнаруживать и предотвращать атаки по подбору SIP паролей.