Trojan:AndroidOS/AdSMS.A

The SMS appears to be targeted to Android users in mainland China, as it pretends to be from a mobile service provider in China and contains Chinese-language text, a translated example of which is as follows:

Dear customer of [network provider], your mobile phone contains security system vulnerability. To increase the security level, please download the updated patch! [link]

The link provided in the SMS leads to the APK for this trojan. At the time of writing, the APK uses the filename htc.apk.

Installation

The trojan is only installed if the user clicks on the link in the malicious SMS. Shown below are the permissions requested by the trojan:

Permissions request by Trojan:AndroidOS/AdSMS.A

Once installed, no icon appears in the phone's applications menu to indicate the malware's presence on the phone, though the trojan will run in the background.

Users may detect its presence by checking the "Manage applications" menu under Settings for the application name andiord.system.providers:

Trojan:AndroidOS/AdSMS.A's listed as 'andiord.system.providers'

Activity

While running, it will download an additional file and configuration file from various malicious sites:

• hxxp://adsms.itodo.cn/[...].aspx?
• hxxp://adsms.yywo.cn/[...].aspx?
• hxxp://adsms.1oo86.net/[...].aspx?
• hxxp://61.164.109.77/[...]/[...].apk

The trojan also obtains the following details from the phone:

• International Mobile Equipment Identity (IMEI)
• Phone number
• SDK version
• Network infromation
• Wi-Fi

And sends the details to remote servers.

The trojan is also capable of reading, writing and sending SMS messages and changing the phone's Wi-Fi state.