Unpacking Diicot - Evolving Campaign Targeting Linux Environments
by Gili Tikochinski and Yaara Shriki
Wiz Threat Research 2024
https://www.wiz.io/blog/diicot-t
Notes |
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Wiz Threat Research |
malware campaign |
Linux malware |
Diicot |
Romania |
cloud |
Cado Security |
Akamai |
BitDefender |
malware has been iterated upon/improved; threat actor is learning/evolving |
Mexals |
self-propagation |
custom UPX packer |
internet scanning |
cryptocurrency mining |
XMRig |
packer |
staged payload |
malware updates |
detection evasion |
persistence |
corrupted UPX checksums break standard unpacking tools |
malware detecting cloud environment by observing Linux distro/version |
threat intelligence |
Discord-based C2 |
HTTP C2 |
cryptocurrency wallet |
mining pool |
Zephyr protocol |
Monero |
Golang-based malware |
custom UPX packer |
cloud-aware payload |
Romanian attribution due to Romanian language used within samples |
OpenSSH |
weak credentials |
YARA |
Azure |
var/tmp.update-logs/Update |
brute-spreader.go |
hidden directory |
Azure Linux |
Amazon Linux |
Linode |
Oracle Cloud |
/var/tmp/cache, client.go |
var/tmp.update-logs/.bisis |
banner grabbing |
IP list |
hardcoded URLs |
port 22 |
VirusTotal |
“first seen” on VirusTotal |
abc123, payload.go |
obfuscation |
magic header – modified UPX changed ‘UPX!" header to YTS\x99 |
upx_dec |
reverse shell |
command and control |
remote command execution |
cron persistence - @reboot, @daily, @monthly |
disown command |
reverse SSH |
bash script |
brute force |
base64 |
User-Agent curl/7.68.0 |
malware obtains CPU count, hostname, architecture, kernel version |
malware obtains host’s IP addresses, username, password, and SSH ports |
malware determines GPU availability |
bisis binary - SSH scanning and brute force tool |
GreyNoise |
raspberry pi |
mongodb |
sonar/sonar123 |
git/git |
awsgui/awsgui |
wang/wang123 |
hive/hive |
nginx/nginx |
tracking crypto wallets and pools |
Validin |
passive DNS |
IoC |
IoCs |
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pauza.digitaldatainsights[.]org |
87.120.114[.]219 |
digital.digitaldatainsights[.]org/.x/black3 |
87.120.116[.]35 |
http[:]//80.76.51[.]5/.NzJjOTY |
digital.digitaldatainsights[.]org |
91.92.250[.]6 |