Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

IoT/Embedded Security //

Botnet

10/1/2018
09:35 AM
Larry Loeb
Larry Loeb
Larry Loeb
50%
50%

Torii Is a New Evolution in Botnet Malware

Move over Mirai. A Bulgarian security researcher and Avast have found a new botnet dubbed Torii, which can bring these types of attacks to a new level.

Bulgarian security researcher Dr. Vesselin Bontchev recently opened his honeytrap nets and found that he had caught something fairly unique and potentially very dangerous -- a new type of botnet.

Bontchev wrote that what he found was unusual, and that the infection vector: "Spreads via Telnet but not your run-of-the-mill Mirai variant or Monero miner... First stage is just a few commands that download a rather sophisticated shell script, disguised as a CSS file."

He also found that the telnet attacks have been coming to his honeypot from Tor exit nodes.

Following the disclosure, Avast researchers jumped on the case, and have given their own take on the matter. Because of the Tor node connection, they named the botnet framework "Torii."

Avast found that the infection script would initially try to discover the architecture of the targeted device. The payload that it would later download would then be the appropriate payload for that device.

Torii uses different commands to get the downloads, including "wget," "ftpget," "ftp," "busybox wget" or "busybox ftpget."

If those don't work, the bot attempts to use FTP for the file transfer. Credentials for this are also embedded in the malware.

The first stage (dropper) payload is an ELF file. Its primary goal is to make what comes in the second stage persistent on the infected site.

The methods the malware uses to achieve this are extremely unusual. Specifically, tt uses six forms of attack and will run all of them every time it infects to assure persistence.

The methods used include:

  • Automatic execution via injected code into ~\.bashrc
  • Automatic execution via "@reboot" clause in crontab
  • Automatic execution as a "System Daemon" service via system
  • Automatic execution via /etc/init and PATH. Once again, it calls itself "System Daemon"
  • Automatic execution via modification of the SELinux Policy Management
  • Automatic execution via /etc/inittab

The list of architectures that Torii supports is fairly wide including devices based on x86_64, x86, ARM, MIPS, Motorola 68k, SuperH, PPC -- with various bit-width and endianness.

The second stage of the infection contains other features such as simple, anti-debugging techniques, data exfiltration and multi-level encryption of communication.

It also tries to get command and control information from top.haletteompson.com, cloud.tillywirtz.com and trade.andrewabendroth.com. It's been found that these three domain names have resolved to an IP address of 66.85.157.90 since September 15.

What Torii does can be used in many ways. It is a modular platform that can enable many exploits, and it very capable in the functions that it provides.

But also of note is that the payload itself is not scanning for other potential targets. That gives it a quite stealthy footprint on the network layer. It doesn't call attention to itself.

Torii is an evolution of what a bot can do. It is trying out its capabilities, but has not yet seemingly been tasked with a specific exploit.

Related posts:

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 7/14/2020
Omdia Research Launches Page on Dark Reading
Tim Wilson, Editor in Chief, Dark Reading 7/9/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Special Report: Computing's New Normal, a Dark Reading Perspective
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
The Threat from the Internetand What Your Organization Can Do About It
The Threat from the Internetand What Your Organization Can Do About It
This report describes some of the latest attacks and threats emanating from the Internet, as well as advice and tips on how your organization can mitigate those threats before they affect your business. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-10287
PUBLISHED: 2020-07-15
The IRC5 family with UAS service enabled comes by default with credentials that can be found on publicly available manuals. ABB considers this a well documented functionality that helps customer set up however, out of our research, we found multiple production systems running these exact default cre...
CVE-2020-10288
PUBLISHED: 2020-07-15
IRC5 exposes an ftp server (port 21). Upon attempting to gain access you are challenged with a request of username and password, however you can input whatever you like. As long as the field isn't empty it will be accepted.
CVE-2020-15780
PUBLISHED: 2020-07-15
An issue was discovered in drivers/acpi/acpi_configfs.c in the Linux kernel before 5.7.7. Injection of malicious ACPI tables via configfs could be used by attackers to bypass lockdown and secure boot restrictions, aka CID-75b0cea7bf30.
CVE-2019-17639
PUBLISHED: 2020-07-15
In Eclipse OpenJ9 prior to version 0.21 on Power platforms, calling the System.arraycopy method with a length longer than the length of the source or destination array can, in certain specially crafted code patterns, cause the current method to return prematurely with an undefined return value. This...
CVE-2019-20908
PUBLISHED: 2020-07-15
An issue was discovered in drivers/firmware/efi/efi.c in the Linux kernel before 5.4. Incorrect access permissions for the efivar_ssdt ACPI variable could be used by attackers to bypass lockdown or secure boot restrictions, aka CID-1957a85b0032.