HKCert
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Hong Kong Google Play Store's Apps Security Risk Report (May 2015)

Release Date: 28 / 05 / 2015
Last Update: 28 / 05 / 2015

 

Hong Kong Computer Emergency Response Team (HKCERT) Coordination Centre cooperates with the National Computer Network Emergency Response Technical Team of China (CNCERT) 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 in Hong Kong area. CNCERT provides us analyzed result, and we collate the detection result and publish security alerts to the public.

 

In the report of May, we have downloaded 200 apps from Play Store, where 5 apps have been identified as high risk. None of them were removed from Play Store (on or before 26-May). 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: 200 apps
  • Unable to download via the system: 0 apps
  • Downloaded date: 5-May 2015
  • List of the downloaded apps: "Appendix 1" [download]

 

Analysis Overview

 

In this analysis, 200 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 having malicious purpose explicitly, which could cause direct harm to systems and users' interests. Suspicious behavior refers to apps having behavior, which could cause direct harm to systems and users' interests, but no malicious behavior can be explicitly identified.

 

 

1. Scanning Result

 

Among the 200 scanned apps, 5 apps were identified as security high risk. These 5 Apps were identified with the following high risk behavior signatures Android.Domob, Android.Adware.Youku, Android.Wiyun, Android.AirPush, Android.Youmi, etc.

 

List of security high risk apps

 

Application

High risk behavior signature / Ad plug-in

Malware detection ratio by VirusTotal

Status #

1) PPS影音HD    (v2.1.1)

Category: Top Free App
Installs: 5,000,000+
High risk behavior description:
obtain SIM status, connect to the Internet, call camera application, get phone content, and delete user data.

Android.Domob

10 / 52
[Link]

Available on play store

2) 优酷XL高清影视    (v1.0.1)

Category: Top Free App
Installs: 100,000+
High risk behavior description:
obtain SIM operator name, obtain SIM serial number, obtain SIM status, enable WiFi automatically, and connect to the Internet.

Android.Adware.Youku

11 / 56
[Link]

Available on play store

3) Magic Candy    (v1.3)

Category: Top Free App, New Free App, Top Free Game, New Free Game
Installs: 500,000+
High risk behavior description:
obtain SIM operator name, obtain SIM serial number, obtain SIM status, read phone number, enable Bluetooth automatically, and connect to the Internet.

Android.Wiyun

9 / 59
[Link]

Available on play store

4) Angels Revenge 3D Free    (v1.2.3)

Category: Top Free Game
Installs: 500,000+
High risk behavior description:
obtain SIM operator name, obtain SIM serial number, obtain SIM status, read phone number, enable Bluetooth automatically, connect to the Internet, and make phone call.

Android.AirPush

11 / 54
[Link]

Available on play store

5) Texas Hold'em Master    (v2.4.0)

Category: New Free App, Top Free Game, New Free Game
Installs: 100,000+
High risk behavior description:
obtain SIM operator name, obtain SIM serial number, obtain SIM status, read phone number, enable Bluetooth automatically, and connect to the Internet.

Android.Youmi

8 / 56
[Link]

Available on play store

 
Remark (#): The status was checked on 26-May. There is no direct relation between the on-shelf status and this report.
 
 
2. High risk behavior signature and Ad plug-in
 

High risk behavior signature and Ad plug-in

High risk behavior

Android.Domob

This is advertisement software bundled with the application, which can insert advertisement in the app, download and install new app, steal user's private information , such as geo-location, IMEI, etc.

Android.Adware.Youku

It is a high risk Ad plug-in, which can steal user's private information, including SIM serial number, SIM status; it can also enable WiFi automatically and connect to the Internet.

Android.Wiyun

This is advertisement software bundled with the application, which can insert advertisement in the app, read user's SMS, send SMS, steal user's private information , such as installed apps, geo-location, etc.

Android.AirPush

It is a high risk Ad plug-in, which can connect to the Internet, make phone call, send out phone information, and modify phone information when it is running.

Android.Youmi

This is advertisement software bundled with the application, which can insert advertisement in the app, download and install new app, steal user's private information , such as geo-location, phone serial number, etc.

 
 
3. High risk app analysis
 
Please refer to "Appendix 2" [download]