
GoldDigger: Accessibility-Abusing Banker Draining APAC Accounts
A mobile-first banking-trojan intrusion on a corporate bring-your-own-device fleet. An employee searching for a government portal sideloaded a trojanized Android installer carrying the GoldDigger banker, granted it Accessibility Service, and the trojan then keylogged, painted fake bank-login overlays, intercepted SMS one-time-passcodes, and beaconed stolen data to a cluster of attacker command-and-control domains, enabling account-draining fraud. Reconstruct the kill chain from the mobile egress SIEM, the mobile threat-defense sensor, and the perimeter firewall, and classify the key ATT&CK mobile techniques.
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Investigation Tasks
Complete each task by investigating alerts and submitting your findings.
Incident brief
0Orient yourself before pivoting into the data. This is a no-answer briefing checkpoint.
Find the sideloaded installer
40Everything later traces back to one file the employee was tricked into installing. Identify the malicious package on the handset.
Identify the permission that unlocked the theft
35The trojan was harmless until the user approved one Android permission. Classify the MITRE ATT&CK technique for the elevation it abused.
Confirm the malware against threat intelligence
35Pin down a huntable file indicator for the banker so every handset can be swept. Provide the SHA-256 of the downloaded installer.
Separate the upload endpoint from the command channel
40The operator kept command polling and stolen-data upload on different hosts. Identify the domain that received the exfiltrated credentials and passcodes.
Classify the passcode theft
35Step-up authentication should have stopped the fraud. Classify how the trojan defeated it on the device.
Name patient zero
35Establish the account to quarantine and reset. Identify the employee whose handset was compromised.
7 tasks · 220 points total
Training Tools
Skills You'll Build
Requires foundational alert triage skills. Multiple data sources to correlate.
Prerequisites
- Basic understanding of security alerts
- Familiarity with SIEM concepts
- Familiarity with Firewall concepts
Ready to investigate?
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