· Droidwatch Security Research team · 4 min read · Static Analysis Deep-Dives sms-stealer ransomware privacy banking-trojan

Static Analysis Deep-Dive #1:  极游市场 — Malicious (74/100)

极游市场 (cn.ggg.market) scored Malicious 74/100 in Droidwatch's static pipeline — 7 critical and 27 high findings, led by sms read + send capability (otp theft

Static Analysis Deep-Dive #1:  极游市场 — Malicious (74/100)

Published 2026-06-07 by the Droidwatch Security Research team


极游市场 (cn.ggg.market) is the highest-scoring sample in this series — Droidwatch's static engine flagged it Malicious at 74/100, off 7 critical and 27 high findings. What pushes it to the top is SMS capability: the app can both read and send text messages, the classic building block for one-time-password theft. The full static breakdown is below — the APK was unzipped, parsed and decompiled but never run, and every line is the platform's own output. It's one entry in our 10-sample static-triage roundup.


Sample at a glance

Field Value
App label  极游市场
Package cn.ggg.market
Version 1.027 (code 1027)
Min / target SDK 4 / 8
Size 1.17 MB
SHA-256 020cb2661836b848f743dafc564ac2b624e7523d26863e5f0ad134fb06edfea8
MD5 74005a5517cb7f0465d5c841d11f8133
Verdict Malicious
Risk score 74 / 100
ML classifier malicious (P(mal)=1.00), model lgbm_binary
Findings raised 74 (7 critical · 27 high · 29 medium)

The verdict, in the platform's words

' 极游市场' (package: cn.ggg.market, v1.027, SDK 4–8) was analyzed and received a risk score of 74/100 (Malicious). SMS reading + sending permissions combined with SmsManager API references suggest capability to intercept bank OTPs and either forward them silently or relay them to a remote server, fully bypassing SMS-based 2FA. The codebase shows significant obfuscation (score 6/10): single-letter class names and dense reflection use, making static analysis difficult. Dynamic analysis is recommended.

What analysis ran

This was a static pass through Droidwatch's pipeline. The stages below produced findings on this sample (stages that found nothing are omitted):

Stage What it inspects Findings
dataflow Source-to-sink data-flow (PII → network/SMS sinks) 15
rules Weighted rule engine (final scoring) 11
ipc IPC / component-security (exported components, PendingIntents, deep links) 9
jadx JADX decompilation deep-scan (secrets, dynamic loading, dangerous calls) 9
manifest AndroidManifest: permissions, components, exported surface, deep links 6
malware_classifier Malware-family heuristics (stalkerware/ransomware/adware/govspyware) 4
storage Insecure data storage (world-readable prefs, external storage, SQLite) 4
attribution Build-path / developer / language attribution 3
crypto Cryptography misuse (weak hashes/ciphers, ECB, insecure RNG, hardcoded keys) 2
packer Packers / protectors, anti-analysis and root-detection (APKiD) 2
banking Banking-trojan behavioral signals (overlay, accessibility, device-admin, dropper) 1
framework Cross-platform framework fingerprinting (Flutter/RN/Unity/native) 1
nsc Network Security Config (cleartext, trust anchors) 1
network URLs / domains / IPs and high-risk network IOCs 1
certificates Code-signing certificate posture 1
strings String indicators, obfuscation score, reflection / dynamic-code refs 1
c2_intel C2 infrastructure intel (AbuseIPDB, Tor, high-risk geos) 1
deobfuscation Base64 / obfuscated-string decoding 1
dex_deep Deep DEX analysis (reflection, dynamic loading, JNI, shell exec) 1
ml_intelligence Independent ML classifier (Androguard features, CICMalDroid-trained) 1

Top findings

Finding Severity Category MASVS / ATT&CK
VirusTotal: Confirmed Malicious 🟥 Critical reputation
Banking Trojan — High Behavioral Signal Score 🟥 Critical banking
Ransomware Behavioral Pattern Detected 🟥 Critical ransomware T1471
Cryptocurrency Payment Address / Ransom Demand Strings 🟥 Critical ransomware T1471
Data Flow: Device ID (IMEI) → SMS Sending (SMS/OTP Forwarding) 🟥 Critical privacy MASVS-STORAGE-2
Data Flow: UI Text Input (possible password) → SMS Sending (SMS/OTP Forwarding) 🟥 Critical privacy MASVS-STORAGE-2
Data Flow: Password Field → HTTP Connection (Data Exfiltration) 🟥 Critical privacy MASVS-STORAGE-2
ML Engine: classified as 'Malicious' — family 'riskware' 🟧 High ml-intelligence
Exported Activity Without Permission: CoverActivity 🟧 High ipc MASVS-PLATFORM-1 · T1416
Exported Activity Without Permission: SearchActivity 🟧 High ipc MASVS-PLATFORM-1 · T1416
Exported Service Without Permission: GGGService 🟧 High ipc MASVS-PLATFORM-1 · T1416
Weak Cipher Algorithm (DES/RC4/Blowfish) 🟧 High crypto MASVS-CRYPTO-1 · T1521

Why this score

The weighted rule engine's top scoring contributions:

Rule Severity Points
VirusTotal: Confirmed Malicious critical +33.2
Banking Trojan — High Behavioral Signal Score critical +26.4
Dropper / Self-Update Capability high +16.4
VirusTotal: Suspicious / Low Detection high +14.8
Banking Trojan — Moderate Behavioral Signals high +11.2
External Storage Write with Sensitive Permission high +9.6

MITRE ATT&CK Mobile mapping

Technique Tactic Why
T1398 Boot or Logon Autostart Persistence Registering to execute automatically after device reboot.
T1406 Obfuscated Files or Information Defense Evasion Using obfuscation to hide malicious code from static analysis.
T1412 Capture SMS Messages Collection Intercepting SMS messages including banking OTP codes.
T1422 System Information Discovery Discovery Malware author attribution indicators: build paths, certificate identity, langua
T1432 Access Contact List Collection Collects sensitive PII or device information.
T1437 Application Layer Protocol: Web Protocols Command and Control Using HTTP/HTTPS for C2 communication.
T1456 Drive-By Compromise Initial Access WebView vulnerabilities enabling JavaScript injection or file access.
T1521 Encrypted Channel: Asymmetric Cryptography Command and Control Weak or broken cryptography that fails to protect data confidentiality.
T1533 Data from Local System Collection Insecure local data storage exposing credentials and PII.
T1544 Ingestion Tool Transfer Command and Control Downloading and installing additional malicious payloads at runtime.

Reproduce it

curl -s -X POST https://droidwatch.app/api/upload \
  -H "X-Upload-Consent: 1" -F "[email protected]" | jq -r .upload_id
# then POST /api/analyze, poll /api/jobs/<id>, read the report (verdict + MITRE + STIX 2.1)

Static-only analysis; the Android dynamic Frida sandbox was not used. Sample from a public 2021 research corpus, referenced by SHA-256. Family attribution is intentionally conservative.

Threat Research

Droidwatch's research team analyzes Android & iOS malware — banking trojans, spyware, droppers and overlay kits — and writes up the static and dynamic signals that give them away. Every post is grounded in real platform output.

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