RedBrowser Trojan

RedBrowser Trojan

« Back to Glossary Index
Visit Us
Follow Me

The RedBrowser Trojan, also known as “RedBrowser,” is a mobile phone malware that targets devices running the Symbian operating system. It gained notoriety in the mid-2000s as one of the early examples of mobile phone malware specifically designed to compromise smartphones and exploit their capabilities for malicious purposes.


The RedBrowser Trojan was distributed as a seemingly harmless mobile application, often disguised as a utility or game, which attracted users to download and install it on their Symbian-based smartphones. It was primarily spread through third-party app stores, malicious websites, or deceptive links shared via email or instant messaging platforms.


Once installed on a victim’s device, the RedBrowser Trojan attempted to conceal its presence by avoiding any visible changes to the device’s functionality. However, behind the scenes, the malware initiated its malicious activities, which included the following:

  1. Premium Rate SMS Fraud: One of the primary objectives of the RedBrowser Trojan was to generate revenue for its creators through premium rate SMS messages. The malware secretly sent unauthorized SMS messages to premium-rate numbers, resulting in significant charges on the victim’s mobile phone bill.
  2. Stealthy Operation: The RedBrowser Trojan aimed to operate covertly to avoid detection by the device owner. It utilized various techniques to hide its activities, such as encrypting its communication with remote servers, disguising sent SMS messages, and evading security software.
  3. Remote Control and Command Execution: The malware allowed remote attackers to take control of the infected device by sending specific commands through SMS messages. This gave the attackers the ability to manipulate the device, initiate additional attacks, or steal sensitive information.

Impact and Mitigation:

The RedBrowser Trojan had a significant impact on infected users, resulting in unexpected and expensive mobile phone bills due to unauthorized premium rate SMS messages. It also raised concerns about the security of mobile devices and the potential for mobile malware to exploit vulnerabilities in smartphone operating systems.

To mitigate the risk of falling victim to mobile phone Trojans like RedBrowser, users are advised to take the following precautions:

  1. Download from Trusted Sources: Only download and install mobile applications from official app stores or reputable sources. Avoid sideloading apps from unknown websites or links.
  2. Keep Software Updated: Regularly update the smartphone’s operating system and security software to ensure that known vulnerabilities are patched.
  3. Exercise Caution with SMS Messages: Be cautious when clicking on links or responding to SMS messages from unknown or suspicious sources.
  4. Use Mobile Security Apps: Install reputable mobile security software that can detect and prevent the installation of malware on the device.
  5. Read App Permissions: Before installing any app, review the permissions it requests. Be wary of apps that request unnecessary permissions that may indicate malicious intent.


The RedBrowser Trojan served as a wake-up call for mobile security concerns in the early days of smartphone usage. It highlighted the need for vigilance and precautionary measures to protect mobile devices from the ever-evolving threat landscape of mobile malware. As the mobile ecosystem continues to grow, users and developers must remain proactive in implementing security best practices to safeguard their devices and data from potential threats.

You may also like...