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Тема

Защита дедика.

Автор: Predat0r 70 сообщений 17638 просмотров
#293753

Добрый день,интересует мануал по защите дедика от брута и остальной "нечести".

#293754

В гугле нашел только это " http://grabberz.com/showthread.php?t=27573 " заинтересовал только последний пост,который убивает процессы.
Хотелось бы еще как-нибудь защитить от брута.

#293757

Спасибо

#293758
"Predat0r" написал:
Спасибо

Я предложил лишь пару возможных вариантов. Опишите подробнее стоящую перед вами задачу.

#293769

del

#293772

Fail2ban не помог.

#293773
"Predat0r" написал:
Fail2ban не помог

каким образом определили?
лог просматривали?

#293777

Оффтоп.

text
Верить нельзя никому...

+ солидарен

#293779

установите: Rkhunter и прогоните им систему
смените пароль на root и обычную учетную запись.
в настройках ssh ограничьте доступ на вход root (только под обычным пользователем сперва) и настройте fail2ban.

#293802

Спасибо,ночью попробую (обратно куча процессов висит(252))

#293825

Немного поправил конфиг fail2ban:

Показать
# Fail2Ban configuration file
#
# Author: Cyril Jaquier
#
# $Revision: 617 $
#

# The DEFAULT allows a global definition of the options. They can be override
# in each jail afterwards.

[DEFAULT]

# "ignoreip" can be an IP address, a CIDR mask or a DNS host. Fail2ban will not
# ban a host which matches an address in this list. Several addresses can be
# defined using space separator.
ignoreip = 127.0.0.1

# "bantime" is the number of seconds that a host is banned.
bantime = 6000

# A host is banned if it has generated "maxretry" during the last "findtime"
# seconds.
findtime = 600

# "maxretry" is the number of failures before a host get banned.
maxretry = 1

# "backend" specifies the backend used to get files modification. Available
# options are "gamin", "polling" and "auto". This option can be overridden in
# each jail too (use "gamin" for a jail and "polling" for another).
#
# gamin: requires Gamin (a file alteration monitor) to be installed. If Gamin
# is not installed, Fail2ban will use polling.
# polling: uses a polling algorithm which does not require external libraries.
# auto: will choose Gamin if available and polling otherwise.
backend = auto


# This jail corresponds to the standard configuration in Fail2ban 0.6.
# The mail-whois action send a notification e-mail with a whois request
# in the body.

[ssh-iptables]

enabled = false
filter = sshd
action = iptables[name=SSH, port=ssh, protocol=tcp]
sendmail-whois[name=SSH, dest=you@mail.com, sender=fail2ban@mail.com]
logpath = /var/log/sshd.log
maxretry = 5

[proftpd-iptables]

enabled = false
filter = proftpd
action = iptables[name=ProFTPD, port=ftp, protocol=tcp]
sendmail-whois[name=ProFTPD, dest=you@mail.com]
logpath = /var/log/proftpd/proftpd.log
maxretry = 6

# This jail forces the backend to "polling".

[sasl-iptables]

enabled = false
filter = sasl
backend = polling
action = iptables[name=sasl, port=smtp, protocol=tcp]
sendmail-whois[name=sasl, dest=you@mail.com]
logpath = /var/log/mail.log

# Here we use TCP-Wrappers instead of Netfilter/Iptables. "ignoreregex" is
# used to avoid banning the user "myuser".

[ssh-tcpwrapper]

enabled = false
filter = sshd
action = hostsdeny
sendmail-whois[name=SSH, dest=you@mail.com]
ignoreregex = for myuser from
logpath = /var/log/sshd.log

# This jail demonstrates the use of wildcards in "logpath".
# Moreover, it is possible to give other files on a new line.

[apache-tcpwrapper]

enabled = false
filter = apache-auth
action = hostsdeny
logpath = /var/log/apache*/*error.log
/home/www/myhomepage/error.log
maxretry = 6

# The hosts.deny path can be defined with the "file" argument if it is
# not in /etc.

[postfix-tcpwrapper]

enabled = false
filter = postfix
action = hostsdeny[file=/not/a/standard/path/hosts.deny]
sendmail[name=Postfix, dest=you@mail.com]
logpath = /var/log/postfix.log
bantime = 300

# Do not ban anybody. Just report information about the remote host.
# A notification is sent at most every 600 seconds (bantime).

[vsftpd-notification]

enabled = false
filter = vsftpd
action = sendmail-whois[name=VSFTPD, dest=you@mail.com]
logpath = /var/log/vsftpd.log
maxretry = 5
bantime = 1800

# Same as above but with banning the IP address.

[vsftpd-iptables]

enabled = false
filter = vsftpd
action = iptables[name=VSFTPD, port=ftp, protocol=tcp]
sendmail-whois[name=VSFTPD, dest=you@mail.com]
logpath = /var/log/vsftpd.log
maxretry = 5
bantime = 1800

# Ban hosts which agent identifies spammer robots crawling the web
# for email addresses. The mail outputs are buffered.

[apache-badbots]

enabled = false
filter = apache-badbots
action = iptables-multiport[name=BadBots, port="http,https"]
sendmail-buffered[name=BadBots, lines=5, dest=you@mail.com]
logpath = /var/www/*/logs/access_log
bantime = 172800
maxretry = 1

# Use shorewall instead of iptables.

[apache-shorewall]

enabled = false
filter = apache-noscript
action = shorewall
sendmail[name=Postfix, dest=you@mail.com]
logpath = /var/log/apache2/error_log

# This jail uses ipfw, the standard firewall on FreeBSD. The "ignoreip"
# option is overridden in this jail. Moreover, the action "mail-whois" defines
# the variable "name" which contains a comma using "". The characters '' are
# valid too.

[ssh-ipfw]

enabled = false
filter = sshd
action = ipfw[localhost=192.168.0.1]
sendmail-whois[name="SSH,IPFW", dest=you@mail.com]
logpath = /var/log/auth.log
ignoreip = 168.192.0.1

# These jails block attacks against named (bind9). By default, logging is off
# with bind9 installation. You will need something like this:
#
# logging {
# channel security_file {
# file "/var/log/named/security.log" versions 3 size 30m;
# severity dynamic;
# print-time yes;
# };
# category security {
# security_file;
# };
# }
#
# in your named.conf to provide proper logging.
# This jail blocks UDP traffic for DNS requests.

[named-refused-udp]

enabled = false
filter = named-refused
action = iptables-multiport[name=Named, port="domain,953", protocol=udp]
sendmail-whois[name=Named, dest=you@mail.com]
logpath = /var/log/named/security.log
ignoreip = 168.192.0.1

# This jail blocks TCP traffic for DNS requests.

[named-refused-tcp]

enabled = false
filter = named-refused
action = iptables-multiport[name=Named, port="domain,953", protocol=tcp]
sendmail-whois[name=Named, dest=you@mail.com]
logpath = /var/log/named/security.log
ignoreip = 168.192.0.1

изменил только maxretry - 1 и bantime - 6000

#293831

Обратно 344 процесса.

#293853

Как ограничить права root?

#293854
Predat0r написал:
Как ограничить права root?

SELinux - спасёт отца русской демократии...

#293856
"Predat0r" написал:
Немного поправил конфиг fail2ban:

этого недостаточно, необходимо включить еще:

text
[ssh-iptables]
enabled  = true

и

text
[ssh-tcpwrapper]
enabled     = true
#293857
"Predat0r" написал:
Как ограничить права root?

vim /etc/ssh/sshd_config

#пользователь которому будет разрешено заходить по SSH
AllowUsers [имя_пользователя]
#Отключить root-доступ
PermitRootLogin no
#Отключить авторизацию с пустым паролем
PermitEmptyPasswords no

#293858

Не нашел выбор пользователя,зато изменил все остальное.
Порт\запрет рута\авторизацию без пароля.

Показать
# $OpenBSD: sshd_config,v 1.80 2008/07/02 02:24:18 djm Exp $

# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.

# This sshd was compiled with PATH=/usr/local/bin:/bin:/usr/bin

# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented. Uncommented options change a
# default value.

Port 55
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::

# Disable legacy (protocol version 1) support in the server for new
# installations. In future the default will change to require explicit
# activation of protocol 1
Protocol 2

# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_dsa_key

# Lifetime and size of ephemeral version 1 server key
#KeyRegenerationInterval 1h
#ServerKeyBits 1024

# Logging
# obsoletes QuietMode and FascistLogging
#SyslogFacility AUTH
SyslogFacility AUTHPRIV
#LogLevel INFO

# Authentication:

#LoginGraceTime 2m
PermitRootLogin no
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

#RSAAuthentication yes
#PubkeyAuthentication yes
#AuthorizedKeysFile .ssh/authorized_keys
#AuthorizedKeysCommand none
#AuthorizedKeysCommandRunAs nobody

# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#RhostsRSAAuthentication no
# similar for protocol version 2
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# RhostsRSAAuthentication and HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes

# To disable tunneled clear text passwords, change to no here!
#PasswordAuthentication yes
PermitEmptyPasswords no
PasswordAuthentication yes

# Change to no to disable s/key passwords
#ChallengeResponseAuthentication yes
ChallengeResponseAuthentication no

# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no
#KerberosUseKuserok yes

# GSSAPI options
#GSSAPIAuthentication no
GSSAPIAuthentication yes
#GSSAPICleanupCredentials yes
GSSAPICleanupCredentials yes
#GSSAPIStrictAcceptorCheck yes
#GSSAPIKeyExchange no

# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
#UsePAM no
UsePAM yes

# Accept locale-related environment variables
AcceptEnv LANG LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES
AcceptEnv LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT
AcceptEnv LC_IDENTIFICATION LC_ALL LANGUAGE
AcceptEnv XMODIFIERS

#AllowAgentForwarding yes
#AllowTcpForwarding yes
#GatewayPorts no
#X11Forwarding no
X11Forwarding yes
#X11DisplayOffset 10
#X11UseLocalhost yes
#PrintMotd yes
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#UsePrivilegeSeparation yes
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#ShowPatchLevel no
#UseDNS yes
#PidFile /var/run/sshd.pid
#MaxStartups 10
#PermitTunnel no
#ChrootDirectory none

# no default banner path
#Banner none

# override default of no subsystems
Subsystem sftp /usr/libexec/openssh/sftp-server

# Example of overriding settings on a per-user basis
#Match User anoncvs
# X11Forwarding no
# AllowTcpForwarding no
# ForceCommand cvs server
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