Written by HAURI Virus Lab
There are various apps installed in our smart phones. They can be sorted into two categories; free or subscribed.
When we search for apps from sources such as Google market, we tend to look for free apps or even pirate versions.
It is a common sense that downloading a pirate app would be dangerous.
But there is danger of using free apps that is not widely known. There are many convenient apps that are free but some of them do cause trouble.
Markets upload free, priced and trial version of apps. Subscribed apps are fully functional with consistent updates. However, free apps contains ad API showing users advertisements to make profit in return.
Some of these ad APIs collect user data such as location, IMEI, IMSI, OS version, country code, rooting progress, language, phone number, hardware model etc and store them in advertiser's database.
It is unknown how they use gathered information but it is certain that we did not agree to such action.
They encrypt some personal information but still they are collection unapproved information.
(DeviceID is encrypted but it seems to be Base64 and it can be decoded)
[Image1] Uploading personal data onto network
Blocking ad API isn't the best solution. As multiple users use free apps, antivirus recognizing it as a threat would cause inconvenience. Similar problem happened when Adware first came out for PC and people couldn't run programs.
Despite the malicious acts, they are proper applications made by corporations, making it difficult for antivirus to define them as malware. Sometimes companies could sue for blocking their apps.
[Image2] App with spam API
Some nations established laws for Adware, which helps to repair malware exceeding standards. However, mobile application related regulations aren't as strong yet making it difficult for antivirus to stop information leak from smart phones. Without standard criteria, it is difficult to categorize malware from apps and fix it.
Of course apps with direct imminent threat are being removed but when the rules are made, people should be informed about it so when suddenly some apps are classified as malware they wouldn't be as confused.
In conclusion, developers should mention about ad API contained within apps they uploaded.
Users should comprehend terms well before downloading and try to avoid installing free apps recklessly to maintain a secure smart phone.