Rewterz Threat Alert – APT Group TA505 “National Tax Code” Malspam Campaign

Severity

Medium

Analysis Summary

TA505 threat group campaign that masquerades as email from “National Tax Inspectorate for interrogation”. 

The initial point of infection sources from an email with the subject “National Tax Code”. Example email:

This spreadsheet contains malicious macros that, once enabled, download and execute the first stage malware “wiskkk.exe”. This executable downloads and executes winserv.exe, the final stage malware, also known as RMS (Remote Manipulator System). RMS is a known remote administration tool by TektonIT and allows complete access to the target system.

Impact

Unauthorized system access

Indicators of Compromise

IP(s) / Hostname(s)

217[.]12[.]201[.]159

Malware Hash (MD5/SHA1/SH256)

• 107DE953B02FB0DD7E31A0B618C3748F2C285070577EF1ABAABEB30AB3153424
• 4423A6B64B8C483B802065A0D14CB21BBFCD3E2D
• 9FDE87763E721EA2EBDAE8AA4C3F6B53
• FD701894E7EC8D8319BC9B32BBA5892B11BDF608C3D04C2F18EFF83419EB6DF0
• 5310C2397BA4C783F7EE9724711A6DA9B5C603B5C9781FFF3407B46725E338B3
• 609B0A416F9B16A6DF9B967DC32CD739402AF31566E019A8FB8ABDF3CB573E30
• 2116152E47309F8A15DC03A417CEF57F
• 0C19E196ACA45CF5CB7CB251498BACC4
• D0FCD4DAEE0BE452884C7FB926A7164F
• 51907D72DFF06693CE403F5A0205126F
• e900a8eafd9449439ad5d8f2032758a5

Email Subject

National Tax Code

Filename

• Documentation-00589019.zip
• document_june2019.zip
• Privat_06.2019.zip
• Personal-0059062019.zip

Remediation

• Block all threat indicators at your respective controls
• Always be suspicious about emails sent by unknown senders
• Never click on the link attachments sent by unknown senders