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
News
-
Intel Unveils Compute Stick
Four-inch-long computer on a stick lets you boot a full Linux system from any HDMI display device.
-
Obama Proposes Personal Data Notification Law
New statute would require companies to report break-ins to consumers.
-
TGXf Project Warns of File Transfer through Screen Pixels
Weird data transfer technique avoids all standard security measures.
-
Industry Giants Announce a Fix for the Password Mess
FIDO alliance declares the beginning of the end for old-style login authentication.
-
Poll: Vote for the Best Open Source Software for Photographers
The Linux New Media Awards have honored the most significant products, projects, people, and organizations for open source/Linux every year since 2000.
-
Debian Gets Forked
Legendary Uber-distro splits over the systemd controversy.
-
Linux Mint Project Releases Mint 17.1
New LTS version offers many refinements for the Cinnamon and Mate desktops and significant improvement under the hood.
-
CeBIT Open Source Forum Call for Papers
One of CeBIT’s most successful forums returns in 2015.
-
TOR Network Isn’t So Anonymous
A new study says it is possible to unmask 81% of TOR users.
-
.NET Goes Open Source
Redmond joins the revolution by turning the .NET Core Runtime into a GitHub project.