Brute-force malware targets email and FTP servers

Researchers find Fort Disco malware variants launching brute force password guessing attacks against POP3 and FTP servers

A piece of malware designed to launch brute-force password guessing attacks against websites built with popular content management systems like WordPress and Joomla has started being used to also attack email and FTP servers.

The malware is known as Fort Disco and was documented in August by researchers from DDoS mitigation vendor Arbor Networks who estimated that it had infected over 25,000 Windows computers and had been used to guess administrator account passwords on over 6,000 WordPress, Joomla and Datalife Engine websites.

Once it infects a computer, the malware periodically connects to a command and control (C&C) server to retrieve instructions, which usually include a list of thousands of websites to target and a password that should be tried to access their administrator accounts.

The Fort Disco malware seems to be evolving, according to a Swiss security researcher who maintains the Abuse.ch botnet tracking service. "Going down the rabbit hole, I found a sample of this particular malware that was brute-forcing POP3 instead of WordPress credentials," he said Monday in a blog post.

The Post Office Protocol version 3 (POP3) allows email clients to connect to email servers and retrieve messages from existing accounts.

The C&C server for this particular Fort Disco variant responds with a list of domain names accompanied by their corresponding MX records (mail exchanger records). The MX records specify which servers are handling email service for those particular domains.

The C&C server also supplies a list of standard email accounts -- usually admin, info and support -- for which the malware should try to brute force the password, the Abuse.ch maintainer said.

"While speaking with the guys over at Shadowserver [an organization that tracks botnets], they reported that they have seen this malware family bruteforcing FTP credentials using the same methodology," he said.

Brute-force password guessing attacks against websites using WordPress and other popular CMSes are relatively common, but they are usually performed using malicious Python or Perl scripts hosted on rogue servers, the researcher said. With this malware, cybercriminals created a way to distribute their attacks across a large number of machines and also attack POP3 and FTP servers, he said.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

Tags securitymalwareintrusionarbor networksAccess control and authentication

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service
Show Comments

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Andrew Teoh

Brother MFC-L9570CDW Multifunction Printer

Touch screen visibility and operation was great and easy to navigate. Each menu and sub-menu was in an understandable order and category

Louise Coady

Brother MFC-L9570CDW Multifunction Printer

The printer was convenient, produced clear and vibrant images and was very easy to use

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Featured Content

Product Launch Showcase

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?