Category Archives: fileless malware

DarkVishnya: Banks attacked through direct connection to local network

While novice attackers, imitating the protagonists of the U.S. drama Mr. Robot, leave USB flash drives lying around parking lots in the hope that an employee from the target company picks one up and plugs it in at the workplace, more experienced cybercriminals prefer not to rely on chance. In 2017-2018, Kaspersky Lab specialists were invited to research a series of cybertheft incidents. Each attack had a common springboard: an unknown device directly connected to the company’s local network. In some cases, it was the central office, in others a regional office, sometimes located in another country. At least eight banks in Eastern Europe were the targets of the attacks (collectively nicknamed DarkVishnya), which caused damage estimated in the tens of millions of dollars.

Each attack can be divided into several identical stages. At the first stage, a cybercriminal entered the organization’s building under the guise of a courier, job seeker, etc., and connected a device to the local network, for example, in one of the meeting rooms. Where possible, the device was hidden or blended into the surroundings, so as not to arouse suspicion.

High-tech tables with sockets are great for planting hidden devices

High-tech tables with sockets are great for planting hidden devices

The devices used in the DarkVishnya attacks varied in accordance with the cybercriminals’ abilities and personal preferences. In the cases we researched, it was one of three tools:

  • netbook or inexpensive laptop
  • Raspberry Pi computer
  • Bash Bunny, a special tool for carrying out USB attacks

Inside the local network, the device appeared as an unknown computer, an external flash drive, or even a keyboard. Combined with the fact that Bash Bunny is comparable in size to a USB flash drive, this seriously complicated the search for the entry point. Remote access to the planted device was via a built-in or USB-connected GPRS/3G/LTE modem.

At the second stage, the attackers remotely connected to the device and scanned the local network seeking to gain access to public shared folders, web servers, and any other open resources. The aim was to harvest information about the network, above all, servers and workstations used for making payments. At the same time, the attackers tried to brute-force or sniff login data for such machines. To overcome the firewall restrictions, they planted shellcodes with local TCP servers. If the firewall blocked access from one segment of the network to another, but allowed a reverse connection, the attackers used a different payload to build tunnels.

Having succeeded, the cybercriminals proceeded to stage three. Here they logged into the target system and used remote access software to retain access. Next, malicious services created using msfvenom were started on the compromised computer. Because the hackers used fileless attacks and PowerShell, they were able to avoid whitelisting technologies and domain policies. If they encountered a whitelisting that could not be bypassed, or PowerShell was blocked on the target computer, the cybercriminals used impacket, and winexesvc.exe or psexec.exe to run executable files remotely.

Verdicts

not-a-virus.RemoteAdmin.Win32.DameWare
MEM:Trojan.Win32.Cometer
MEM:Trojan.Win32.Metasploit
Trojan.Multi.GenAutorunReg
HEUR:Trojan.Multi.Powecod
HEUR:Trojan.Win32.Betabanker.gen
not-a-virus:RemoteAdmin.Win64.WinExe
Trojan.Win32.Powershell
PDM:Trojan.Win32.CmdServ
Trojan.Win32.Agent.smbe
HEUR:Trojan.Multi.Powesta.b
HEUR:Trojan.Multi.Runner.j
not-a-virus.RemoteAdmin.Win32.PsExec

Shellcode listeners

tcp://0.0.0.0:5190
tcp://0.0.0.0:7900

Shellcode connects

tcp://10.**.*.***:4444
tcp://10.**.*.**:4445
tcp://10.**.*.**:31337

Shellcode pipes

\\.\xport
\\.\s-pipe

Securelist: DarkVishnya: Banks attacked through direct connection to local network

While novice attackers, imitating the protagonists of the U.S. drama Mr. Robot, leave USB flash drives lying around parking lots in the hope that an employee from the target company picks one up and plugs it in at the workplace, more experienced cybercriminals prefer not to rely on chance. In 2017-2018, Kaspersky Lab specialists were invited to research a series of cybertheft incidents. Each attack had a common springboard: an unknown device directly connected to the company’s local network. In some cases, it was the central office, in others a regional office, sometimes located in another country. At least eight banks in Eastern Europe were the targets of the attacks (collectively nicknamed DarkVishnya), which caused damage estimated in the tens of millions of dollars.

Each attack can be divided into several identical stages. At the first stage, a cybercriminal entered the organization’s building under the guise of a courier, job seeker, etc., and connected a device to the local network, for example, in one of the meeting rooms. Where possible, the device was hidden or blended into the surroundings, so as not to arouse suspicion.

High-tech tables with sockets are great for planting hidden devices

High-tech tables with sockets are great for planting hidden devices

The devices used in the DarkVishnya attacks varied in accordance with the cybercriminals’ abilities and personal preferences. In the cases we researched, it was one of three tools:

  • netbook or inexpensive laptop
  • Raspberry Pi computer
  • Bash Bunny, a special tool for carrying out USB attacks

Inside the local network, the device appeared as an unknown computer, an external flash drive, or even a keyboard. Combined with the fact that Bash Bunny is comparable in size to a USB flash drive, this seriously complicated the search for the entry point. Remote access to the planted device was via a built-in or USB-connected GPRS/3G/LTE modem.

At the second stage, the attackers remotely connected to the device and scanned the local network seeking to gain access to public shared folders, web servers, and any other open resources. The aim was to harvest information about the network, above all, servers and workstations used for making payments. At the same time, the attackers tried to brute-force or sniff login data for such machines. To overcome the firewall restrictions, they planted shellcodes with local TCP servers. If the firewall blocked access from one segment of the network to another, but allowed a reverse connection, the attackers used a different payload to build tunnels.

Having succeeded, the cybercriminals proceeded to stage three. Here they logged into the target system and used remote access software to retain access. Next, malicious services created using msfvenom were started on the compromised computer. Because the hackers used fileless attacks and PowerShell, they were able to avoid whitelisting technologies and domain policies. If they encountered a whitelisting that could not be bypassed, or PowerShell was blocked on the target computer, the cybercriminals used impacket, and winexesvc.exe or psexec.exe to run executable files remotely.

Verdicts

not-a-virus.RemoteAdmin.Win32.DameWare
MEM:Trojan.Win32.Cometer
MEM:Trojan.Win32.Metasploit
Trojan.Multi.GenAutorunReg
HEUR:Trojan.Multi.Powecod
HEUR:Trojan.Win32.Betabanker.gen
not-a-virus:RemoteAdmin.Win64.WinExe
Trojan.Win32.Powershell
PDM:Trojan.Win32.CmdServ
Trojan.Win32.Agent.smbe
HEUR:Trojan.Multi.Powesta.b
HEUR:Trojan.Multi.Runner.j
not-a-virus.RemoteAdmin.Win32.PsExec

Shellcode listeners

tcp://0.0.0.0:5190
tcp://0.0.0.0:7900

Shellcode connects

tcp://10.**.*.***:4444
tcp://10.**.*.**:4445
tcp://10.**.*.**:31337

Shellcode pipes

\\.\xport
\\.\s-pipe



Securelist

New ‘Under the Radar’ report examines modern threats and future technologies

As if you haven’t heard it enough from us, the threat landscape is changing. It’s always changing, and usually not for the better.

The new malware we see being developed and deployed in the wild have features and techniques that allow them to go beyond what they were originally able to do, either for the purpose of additional infection or evasion of detection.

To that end, we decided to take a look at a few of these threats and pick apart what about them makes them difficult to detect, remaining just out of sight and able to silently spread across an organization.

 Download: Under the Radar: The Future of Undetected Malware

We then examine what technologies are unprepared for these threats, which modern tech is actually effective against these new threats, and finally, where the evolution of these threats might eventually lead.

The threats we discuss:

  • Emotet
  • TrickBot
  • Sorebrect
  • SamSam
  • PowerShell, as an attack vector

While discussing these threats, we also look at where they are most commonly found in the US, APAC, and EMEA regions.

Emotet 2018 detections in the United States

Emotet 2018 detections in the United States

In doing so, we discovered interesting trends that create new questions, some of which are clear and others that need more digging. Regardless, it is evident that these threats are not old hat, but rather making bigger and bigger splashes as the year goes on, in interesting and sometimes unexpected ways.

Sorebrect ransomware detections in APAC regionSorebrect ransomware detections in APAC region

Though the spread and capabilities of future threats are unknown, we have to prepare people to protect their data and experiences online. Unfortunately, many older security solutions will not be able to combat future threats, let alone what is out there now.

Not all is bad news in security, though, as we do have a lot going for us as in technological developments and innovations in modern features. For example:

  • Behavioral detection
  • Blocking at delivery
  • Self-defense modes

These features are effective at combating today’s threats and will soon be needed to build the basis for future developments, such as:

  • Artificial Intelligence being used to develop, distribute, or control malware
  • The continued development of fileless and “invisible” malware
  • Businesses becoming worm food for future malware

Download: Under the Radar: The Future of Undetected Malware

The post New ‘Under the Radar’ report examines modern threats and future technologies appeared first on Malwarebytes Labs.

Hacked Without a Trace: The Threat of Fileless Malware

Malware. The word alone makes us all cringe as we instantly relate it to something malicious happening on our computers or devices. Gone are the days when we thought the

The post Hacked Without a Trace: The Threat of Fileless Malware appeared first on The Cyber Security Place.