A Android chat application which claims to be a safe platform messaging, spies on users and saves data their in an unsafe location that is publicly available. The reason for the application Welcome Chat, which seems to be targeting users from a specific area and is based on open source code for recording calls, stealing messages and tracking them users.
Normal permissions for a chat application
The developers of Welcome Chat promoted it as a secure communication solution that is available from Google Play store. The chat application intended for Arabic-speaking users. Note that some countries in the Middle East ban this type of application.
The company's researchers ESET found the Android chat application he also does many things, which he does not officially mention or advertise. They also saw the app was never part of the official Android store.
Applications outside the Play Store require them users allow installation from unknown sources, which is the case with Welcome Chat.
If users follow this procedure, the chat application requests permission to send and view SMS messages, access files, record audio, and access in the contacts and location of the device. These permissions are normal for a chat app.
The application uses open source code to spy on users
Once the user gives permission, Welcome Chat starts sends information about device and communicate with its command and control (C2) server every five minutes.
Researchers say that monitor communication with other users Welcome Chat is at the heart of this malicious application. Other features include:
- theft of sent and received messages
- theft of call history
- theft of the victim's contact list
- photo theft
- theft of recorded telephone calls
- sending location data and other system information
The researchers found that much of the code used for espionage came from public sources (eg open-source projects, etc.).
Whoever created Welcome Chat did not spend much time. He probably looked at Internet for the desired espionage operation and used the first code he found.
This conclusion comes from the "age" of the code, which in some cases is available to the public for at least five years. Call logging and location tracking, for example, are "eight years old".
User data is accessible
"The data are not encrypted and therefore, not only are they available to the attacker, but also to anyone on the same network. " says the ESET researcher, Lukas Stefanko.
The chat application database includes everything except the user account password: names, addresses e-mail, phone numbers, device tokens, profile pictures, messages, and friends list.
Initially, researchers believed that Welcome Chat was a legitimate chat application that had been infected by criminals. So they tried to warn them developers. However, they found a pure variant in VirusTotal and realized that the application was created from scratch to spy users.
Although there is no strong evidence, the chat app may be the work of the same team behind the BadPatch, a spy campaign launched in 2017 targeting users in the Middle East.