Linux Analysis Report
na.elf

Overview

General Information

Sample name: na.elf
Analysis ID: 1530545
MD5: 37db8aaa1261f99aa257c02c4df5c574
SHA1: 392f68947e899060d8b700a96d7593581d7a2aaf
SHA256: c1622e5b492929782334c8d55380f5e25f5ab36aa287081372d3d2d1542572fe
Tags: elfuser-abuse_ch
Infos:

Detection

Score: 64
Range: 0 - 100
Whitelisted: false

Signatures

Multi AV Scanner detection for submitted file
Connects to many ports of the same IP (likely port scanning)
Deletes system log files
Sample tries to access files in /etc/config/ (typical for OpenWRT routers)
Sends malformed DNS queries
Creates hidden files and/or directories
Detected TCP or UDP traffic on non-standard ports
Found strings indicative of a multi-platform dropper
Sample has stripped symbol table
Sample listens on a socket
Uses the "uname" system call to query kernel version information (possible evasion)

Classification

AV Detection
barindex
Multi AV Scanner detection for submitted file
Source: na.elf ReversingLabs: Detection: 26%
Source: na.elf Virustotal: Detection: 23% Perma Link
Found strings indicative of a multi-platform dropper
Source: na.elf String: ash|login|wget|curl|tftp|ntpdate
Source: na.elf String: /proc//exe|ash|login|wget|curl|tftp|ntpdate/fdsocket|proc/usr/bin/usr/sbin/system/mnt/mtd/app/org/z/zbin/home/app/dvr/bin/duksan/userfs/mnt/app/usr/etc/dvr/main/usr/local/var/bin/tmp/sqfs/z/bin/dvr/mnt/mtd/zconf/gm/bin/home/process/var/challenge/usr/lib/lib/systemd//usr/lib/systemd/system/system/bin//mnt//home/helper/home/davinci/usr/libexec//sbin//bin/

Networking
barindex
Connects to many ports of the same IP (likely port scanning)
Source: global traffic TCP traffic: 38.60.249.66 ports 3,4,6,7,9,49376
Sends malformed DNS queries
Source: global traffic DNS traffic detected: malformed DNS query: 75cents.libre. [malformed]
Detected TCP or UDP traffic on non-standard ports
Source: global traffic TCP traffic: 192.168.2.13:33622 -> 38.60.249.66:49376
Sample listens on a socket
Source: /tmp/na.elf (PID: 5507) Socket: 127.0.0.1:1234 Jump to behavior
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown TCP traffic detected without corresponding DNS query: 38.60.249.66
Source: unknown UDP traffic detected without corresponding DNS query: 63.231.92.27
Source: unknown UDP traffic detected without corresponding DNS query: 161.97.219.84
Source: unknown UDP traffic detected without corresponding DNS query: 116.203.104.203
Source: unknown UDP traffic detected without corresponding DNS query: 63.231.92.27
Source: unknown UDP traffic detected without corresponding DNS query: 192.3.165.37
Source: unknown UDP traffic detected without corresponding DNS query: 130.61.64.122
Source: unknown UDP traffic detected without corresponding DNS query: 116.203.104.203
Source: unknown UDP traffic detected without corresponding DNS query: 1.1.1.1
Source: unknown UDP traffic detected without corresponding DNS query: 1.1.1.1
Source: global traffic DNS traffic detected: DNS query: 75cents.libre. [malformed]
Source: global traffic DNS traffic detected: DNS query: kr2ddnsnet.dyn
Source: global traffic DNS traffic detected: DNS query: daisy.ubuntu.com
Sample has stripped symbol table
Source: ELF static info symbol of initial sample .symtab present: no
Source: classification engine Classification label: mal64.troj.evad.linELF@0/0@5/0

Data Obfuscation
barindex
Sample tries to access files in /etc/config/ (typical for OpenWRT routers)
Source: /tmp/na.elf (PID: 5513) File: /etc/config Jump to behavior
Creates hidden files and/or directories
Source: /tmp/na.elf (PID: 5513) Directory: /root/.cache Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /root/.ssh Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /root/.config Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /root/.local Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /tmp/.X11-unix Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /tmp/.Test-unix Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /tmp/.font-unix Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /tmp/.ICE-unix Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /tmp/.XIM-unix Jump to behavior
Source: /tmp/na.elf (PID: 5513) Directory: /etc/.java Jump to behavior

Hooking and other Techniques for Hiding and Protection
barindex
Deletes system log files
Source: /tmp/na.elf (PID: 5513) Log files deleted: /var/log/kern.log Jump to behavior
Uses the "uname" system call to query kernel version information (possible evasion)
Source: /tmp/na.elf (PID: 5507) Queries kernel information via 'uname': Jump to behavior
Source: na.elf, 5507.1.00007ffc86067000.00007ffc86088000.rw-.sdmp Binary or memory string: x86_64/usr/bin/qemu-arm/tmp/na.elfSUDO_USER=saturninoPATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/binDISPLAY=:1.0XAUTHORITY=/run/user/1000/gdm/XauthoritySUDO_UID=1000TERM=xterm-256colorCOLORTERM=truecolorLOGNAME=rootUSER=rootLANG=en_US.UTF-8SUDO_COMMAND=/bin/bashHOME=/rootMAIL=/var/mail/rootSUDO_GID=1000SHELL=/bin/bash/tmp/na.elf
Source: na.elf, 5507.1.00005651fc612000.00005651fc760000.rw-.sdmp Binary or memory string: QV!/etc/qemu-binfmt/arm
Source: na.elf, 5507.1.00005651fc612000.00005651fc760000.rw-.sdmp Binary or memory string: /etc/qemu-binfmt/arm
Source: na.elf, 5507.1.00007ffc86067000.00007ffc86088000.rw-.sdmp Binary or memory string: /usr/bin/qemu-arm

No Screenshots

  • No. of IPs < 25%
  • 25% < No. of IPs < 50%
  • 50% < No. of IPs < 75%
  • 75% < No. of IPs

Contacted Public IPs

IP Domain Country Flag ASN ASN Name Malicious
116.203.104.203
 unknown Germany
24940 HETZNER-ASDE false
130.61.64.122
 unknown United States
31898 ORACLE-BMC-31898US false
38.60.249.66
 unknown United States
174 COGENT-174US true

Contacted Domains

Name IP Active
daisy.ubuntu.com 162.213.35.24 true
75cents.libre. [malformed] unknown unknown
kr2ddnsnet.dyn unknown unknown