Hong Kong Google Play Store's Apps Security Risk Report (July 2013)

Hong Kong Computer Emergency Response Team (HKCERT) Coordination Centre cooperates with the National Institute of Network and Information Security (NINIS) for detecting malicious and suspicious behaviors of Apps from the Google Play Store, in order to study the security risk of apps in the Google Play Store for Hong Kong area. NINIS provides us analyzed result, and we collate the detection result and publishes security alerts to the public.

In the report of July, 186 apps were downloaded from Play Store, where 3 apps have been identified as high risk. The detail of report is shown as follow.

Target scope:

• Top 50 Free Applications in Hong Kong area
• Top 50 New Free Applications in Hong Kong area
• Top 50 Free Games in Hong Kong area
• Top 50 New Free Games in Hong Kong area

Scanned Apps

• Successful downloaded and scanned: 186 apps
• Unable to download via the system: 14 apps
• Downloaded date: 5-July 2013
• List of the downloaded apps: "Appendix 1"

Analysis Overview

In this analysis, 186 apps were scanned for bad behaviors. Based on the level of security threat, the apps were divided into 2 categories: apps with malicious and apps with suspicious behaviors. Malicious behavior refers to apps behavior pose malicious level of security risk, which can be identified explicitly, that causes security threat to users. Suspicious behavior refers to apps behavior pose certain level of security risk, but no malicious behavior can be explicitly identified.

1. Scanning Result

Among the 186 scanned apps, 3 apps were identified as security high risk. These 3 Apps were identified with a high risk behavior signature, a.remote.GingerMaster or Android.Trojan.InfoStealer.

• a.remote.GingerMaster, can connect to the Internet in background, and get the commands from server, to undermine the systems, disclose the information of IMEI, IMSI, and geo-location, etc. Also, it illegally tries to gain the root permission, and install malware silently.
• Android.Trojan.InfoStealer, is an online banking fraud, which is a Trojan generation tool. Intruder can modify the tool based on the property of target game, and produce a Trojan for the target game.

List of security high risk apps

Remark (*): The plug-in is in security high risk.

2. High risk behavior signature and Ad plug-in

3. Parts of high risk app analysis

Please refer to "Appendix 2".