Fighting dictionary attacks with Sshutout and Fail2ban
Closing the Book

© Andriy Solovyov, Fotolia
Services that require a username and password for login are potential targets for dictionary attacks. Sshutout and Fail2ban introduce time penalties for invalid attempts.
Sshutout [1] is a daemon written in C that checks a logfile for invalid SSH logins at frequent intervals. If Sshutout discovers a pattern of failed login attempts by a client, it blocks the client according to iptables rules. After a configurable delay, the penalty is automatically revoked.
Activating the Ban
All it takes to install the 32KB tarball is the usual make; make install.
The daemon is located in /usr/local/sbin after the install, and its configuration file is /etc/sshutout.conf.
[...]
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

News
-
RingReaper Malware Poses Danger to Linux Systems
A new kind of malware exploits modern Linux kernels for I/O operations.
-
Happy Birthday, Linux
On August 25, Linux officially turns 34.
-
VirtualBox 7.2 Has Arrived
With early support for Linux kernel 6.17 and other new additions, VirtualBox 7.2 is a must-update for users.
-
Linux Mint 22.2 Beta Available for Testing
Some interesting new additions and improvements are coming to Linux Mint. Check out the Linux Mint 22.2 Beta to give it a test run.
-
Debian 13.0 Officially Released
After two years of development, the latest iteration of Debian is now available with plenty of under-the-hood improvements.
-
Upcoming Changes for MXLinux
MXLinux 25 has plenty in store to please all types of users.
-
A New Linux AI Assistant in Town
Newelle, a Linux AI assistant, works with different LLMs and includes document parsing and profiles.
-
Linux Kernel 6.16 Released with Minor Fixes
The latest Linux kernel doesn't really include any big-ticket features, just a lot of lines of code.
-
EU Sovereign Tech Fund Gains Traction
OpenForum Europe recently released a report regarding a sovereign tech fund with backing from several significant entities.
-
FreeBSD Promises a Full Desktop Installer
FreeBSD has lacked an option to include a full desktop environment during installation.