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Grandoreiro, a banking trojan with roots in Brazil, has evolved into a global malware threat. Initially targeting Latin American financial institutions, it now poses risks to organizations worldwide. IBM X-Force Threat Intelligence researchers, including Golo Mühr, have uncovered its sophisticated techniques, including phishing campaigns, social engineering, and evasion tactics.
You Should Know:
1. Grandoreiro’s Infection Chain
- Phishing Emails: Delivers malicious attachments (e.g., PDFs, ZIP files).
- Malicious Macros: Uses Office documents to execute PowerShell scripts.
- Persistence: Modifies registry keys (
HKCU\Software\Microsoft\Windows\CurrentVersion\Run).
Commands to Detect & Mitigate:
Check running processes for suspicious activity ps aux | grep -i "powershell|wscript|cscript" Analyze registry for persistence reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Run Monitor network connections netstat -ano | findstr ESTABLISHED
2. Evasion Techniques
- Process Hollowing: Injects into legitimate processes (e.g.,
explorer.exe). - Anti-Sandbox Checks: Detects virtualized environments.
Detection Commands (Linux/Windows):
Linux: Check for unusual child processes pstree -p | grep -i "explorer|powershell" Windows: List loaded DLLs tasklist /m
3. Data Exfiltration
- C2 Communication: Uses HTTPS to blend with legitimate traffic.
- Keylogging: Captures banking credentials.
Network Analysis:
Capture HTTP/S traffic (Linux)
tcpdump -i eth0 'port 443 or port 80' -w grandoreiro_traffic.pcap
Windows: Check active connections
Get-NetTCPConnection | Where-Object {$_.State -eq "Established"}
What Undercode Say
Grandoreiro exemplifies the shift in cybercrime—regional threats going global. Defenders must:
– Monitor PowerShell activity (Get-WinEvent -LogName "Microsoft-Windows-PowerShell/Operational").
– Block malicious macros via GPO.
– Use YARA rules to detect Grandoreiro payloads.
– Inspect TLS traffic for anomalies (e.g., JA3 fingerprinting).
Expected Output:
- Suspicious process: powershell.exe (PID 1234) - Registry key modified: HKCU...\Run\GrandoreiroLoader - C2 IP: 185.xx.xx.xx (HTTPS)
Reference:
The Global Malware Menace Born in Brazil
(End of report)
References:
Reported By: Kevin Albano – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
