Crutch

S0538

Malware.View on attack.mitre.org

About this malware

Crutch is a backdoor designed for document theft that has been used by Turla since at least 2015.

Techniques used15

Procedure examples15

TechniqueProcedure example
T1005
Data from Local System

Crutch can exfiltrate files from compromised systems.

T1008
Fallback Channels

Crutch has used a hardcoded GitHub repository as a fallback channel.

T1020
Automated Exfiltration

Crutch has automatically exfiltrated stolen files to Dropbox.

T1025
Data from Removable Media

Crutch can monitor removable drives and exfiltrate files matching a given extension list.

T1036.004
Masquerade Task or Service

Crutch has established persistence with a scheduled task impersonating the Outlook item finder.

T1041
Exfiltration Over C2 Channel

Crutch can exfiltrate data over the primary C2 channel (Dropbox HTTP API).

T1053.005
Scheduled Task

Crutch has the ability to persist using scheduled tasks.

T1071.001
Web Protocols

Crutch has conducted C2 communications with a Dropbox account using the HTTP API.

T1074.001
Local Data Staging

Crutch has staged stolen files in the C:\AMD\Temp directory.

T1102.002
Bidirectional Communication

Crutch can use Dropbox to receive commands and upload stolen data.

T1119
Automated Collection

Crutch can automatically monitor removable drives in a loop and copy interesting files.

T1120
Peripheral Device Discovery

Crutch can monitor for removable drives being plugged into the compromised machine.

T1560.001
Archive via Utility

Crutch has used the WinRAR utility to compress and encrypt stolen files.

T1567.002
Exfiltration to Cloud Storage

Crutch has exfiltrated stolen data to Dropbox.

T1574.001
DLL

Crutch can persist via DLL search order hijacking on Google Chrome, Mozilla Firefox, or Microsoft OneDrive.

Groups that use it1

Campaigns0

None recorded.

References1

  1. ESET Crutch December 2020 Open source
    Faou, M. (2020, December 2). Turla Crutch: Keeping the “back door” open. Retrieved December 4, 2020.

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