HKCert
Security Blog

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

Release Date: 28 / 08 / 2013
Last Update: 27 / 09 / 2013

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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 in Hong Kong area. NINIS provides us analyzed result, and we collate the detection result and publish security alerts to the public.

 

In the report of August, we have downloaded 184 apps from Play Store, where 6 apps have been identified as high risk. 3 of them were removed from Play Store (on or before 20-August). 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: 184 apps
  • Unable to download via the system: 16 apps
  • Downloaded date: 5-August 2013
  • List of the downloaded apps: "Appendix 1" [download]

 

Analysis Overview

 

In this analysis, 184 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 184 scanned apps, 6 apps were identified as security high risk. These 6 Apps were identified with a high risk behavior signature, Android.Trojan.Genericor; and high risk Ad plug-in, Android.Adware.Plankton, Android.Adware.Adwo, Android.Adware.AirPush and Android.Counterclank. The behaviors can put user's device and its information at risk. It can also steal user's private information, such as phone number, network status, and email account.

 

List of security high risk apps

 

Application

High risk behavior signature / Ad plug-in

Malware detection ratio

Status #

1. 空空高清影院(激情版) v2.1.4
Category: New Free Applications
Installs: 50,000-250,000
High risk behavior description:
It is an Ad plug-in bundled with App, which can steal user's private information, such as phone number and email address, and send to cooperative companies.

Android.Trojan.Generic,
Android.Counterclank,
Android.Adware.Plankton,
Android.Adware.AirPush

13/46
[link]

Removed from play store

2. 姓名分析專業版-紫微+姓名 寶寶起名 v2.2.5
Category: New Free Applications
Installs: 10,000-50,000
High risk behavior description:
It advertises application on pop-up ads and commercial ads, which can be downloaded and installed without getting user's permission. It can steal user's private information.

Android.Adware.Adwo

11/44
[link]

Available on play store

3. 娱乐搜索_免费电影电视剧动漫综艺资源 v2.5.4
Category: New Free Applications
Installs: 5,000-10,000
High risk behavior description:
It is an Ad plug-in bundled with App, which can steal user's private information, such as phone number and email address, and send to cooperative companies.

Android.Trojan.Generic,
Android.Adware.Plankton,
Android.Adware.AirPush

12/44
[link]

Removed from play store

4. 瘋狂猜成語 v1.35
Category: Top Free Games
Installs: >250,000
High risk behavior description:
It advertises application on pop-up ads and commercial ads, which can be downloaded and installed without getting user's permission. It can steal user's private information.

Android.Trojan.Generic,
Android.Adware.Adwo

13/42
[link]

Available on play store

5. 性感 动漫 v1.1
Category: Top Free Games
Installs: 10,000-50,000
High risk behavior description:
It is an Ad plug-in bundled with App, which can steal user's private information, such as phone number and email address, and send to cooperative companies.

Android.Counterclank,
Android.Adware.Plankton,
Android.Adware.AirPush

17/46
[link]

Removed from play store

6. Virtual Surgery : Surgery Game v1.1
Category: New Free Games
Installs: >250,000
High risk behavior description:
It is an Ad plug-in bundled with App, which can steal user's private information, such as phone number and email address, and send to cooperative companies.

Android.Trojan.Generic,
Android.Counterclank,
Android.Adware.Plankton

15/46
[link]

Available on play store

Remark (#): The status was checked on 20-August.
 
2. High risk behavior signature and Ad plug-in
 

High risk behavior signature and Ad plug-in

High risk behavior

Android.Adware.Plankton.A

It is an Ad plug-in bundled with App, which can steal user's private information, such as phone number and email address, and send to cooperative companies. This behavior is called "aggressive advertisement", which forces displaying ads on the main screen.

Android.Adware.Adwo.A

It is an Ad plug-in bundled with App, which can steal user's private information, such as phone number and email address, and send to cooperative companies.

Android.Counterclank.A

It advertises application on pop-up ads and commercial ads, which can be downloaded and installed without getting user's permission. It can steal user's private information.

Android.Adware.AirPush.G

This is an advertisement framework. It can aggressively push ad to device's notification bar. It can modify browser's bookmark, and remove icon on the main screen. The ads will ask for money. Some ads showed in the notification bar will lure user to subscribe and pay for SMS service. Three common luring ads are 1) fake shop, 2) fake free call service, 3) system notification impersonation

Android.Trojan.Generic

Android.Trojan.Generic is a malicious backdoor Trojan, which runs in the background. It allows remote access to the infected system. It will collect and steal sensitive information, such as Internet activities, account/password setting, geo-location, operator name, system version, device model, IMEI, etc.

 
3. Parts of high risk app analysis
 
Please refer to "Appendix 2" [download]