An insidious spam botnet attacks Charly
BOT POSSE
While going about his normal duties, Linux Magazine author Charly Kühnast was hit with a mean attack. Charly’s separate anti-spam server, which sits in front of his mail server, saved him from the mail storm.
A sunny Tuesday in July. I’m just typing my Sysadmin column for Linux Magazine. It’s 2.00 pm by the time I take a glance at the monitor that gives me the latest load and traffic data for the critical servers I manage. Lo and behold, the reject line in the spam filter graph has just skyrocketed (See Figure 1). The article will have to wait. The server is rejecting large quantities of mail at an early stage of the SMTP dialog. I suspect a wave of spam with clumsily spoofed envelopes. That’s nothing new: for each legitimate email I receive, I get at least two spam mails. But I still decide to open an SSH connection to the spam filter, which is running on a separate machine, and I can’t believe my eyes when I discover 140 parallel SMTP connections. That’s ten times the normal level. And it’s unusual for the server just to drop the connections like that.
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
News
-
Mageia 9 Beta 2 Ready for Testing
The latest beta of the popular Mageia distribution now includes the latest kernel and plenty of updated applications.
-
KDE Plasma 6 Looks to Bring Basic HDR Support
The KWin piece of KDE Plasma now has HDR support and color management geared for the 6.0 release.
-
Bodhi Linux 7.0 Beta Ready for Testing
The latest iteration of the Bohdi Linux distribution is now available for those who want to experience what's in store and for testing purposes.
-
Changes Coming to Ubuntu PPA Usage
The way you manage Personal Package Archives will be changing with the release of Ubuntu 23.10.
-
AlmaLinux 9.2 Now Available for Download
AlmaLinux has been released and provides a free alternative to upstream Red Hat Enterprise Linux.
-
An Immutable Version of Fedora Is Under Consideration
For anyone who's a fan of using immutable versions of Linux, the Fedora team is currently considering adding a new spin called Fedora Onyx.
-
New Release of Br OS Includes ChatGPT Integration
Br OS 23.04 is now available and is geared specifically toward web content creation.
-
Command-Line Only Peropesis 2.1 Available Now
The latest iteration of Peropesis has been released with plenty of updates and introduces new software development tools.
-
TUXEDO Computers Announces InfinityBook Pro 14
With the new generation of their popular InfinityBook Pro 14, TUXEDO upgrades its ultra-mobile, powerful business laptop with some impressive specs.
-
Linux Kernel 6.3 Release Includes Interesting Features
Although it's not a Long Term Release candidate, Linux 6.3 includes features that will benefit end users.