El malware for Android The threat of cybercrime has evolved significantly in recent years, going from simple Trojans that steal text messages to complex viruses capable of taking complete control of our mobile devices, sending offensive messages without our consent, and causing significant financial losses. Although we're increasingly hearing about viruses like Faketoken or SMSFactory, the reality is that there are dozens of threats that can affect both your privacy and your wallet, and that use the most ingenious methods to spread and go unnoticed.
In this article you will discover in detail How Android viruses that send offensive messages work, the most dangerous variants, how to detect malware on your phone, infection and spread methods, the most common symptoms, and the essentials: best practices and tools to protect yourself and eliminate any threat. All of this is explained in a comprehensive and organized manner, based on the experience of leading cybersecurity laboratories and the latest trends.
How does an Android virus that sends offensive messages work?
The onset of Viruses such as Faketoken, SMSFactory, Joker and other SMS Trojans This has represented a qualitative leap in the malware landscape. They are no longer content with traditional banking information theft. They now have the capabilities to:
- Sending SMS messages with offensive content or spam to random numbers from the address book or to unknown international numbers.
- Subscribe the user to premium services SMS messages without your permission, resulting in high charges on your phone bill.
- Spread the virus automatically through messages to the user's contacts, multiplying their reach.
- Steal personal and banking information impersonating legitimate apps and capturing credentials through fake windows.
- Top up the mobile balance using the victim's bank card to continue sending paid text messages.
This evolution is due to the fact that cybercriminals are looking for maximum economic benefit, taking advantage of users' ignorance and carelessness and the vulnerabilities of a system as widespread as Android.
Main variants of SMS malware on Android: Faketoken, SMSFactory, and Joker
Let's take a closer look at the three most notorious and disturbing types of malware, including how they operate, their distinguishing characteristics, and why they're so difficult to stop.
Faketoken: From Banking Trojan to Offensive Message Generator
The Faketoken malware, first detected as banking trojan, quickly evolved to specialize in hijacking Android devices. Initially, it intercepted OTP (One Time Password) messages to authorize fraudulent online banking transfers, but with newer versions, it has acquired much more damaging capabilities:
- It requests permission to become the "default SMS app," allowing it to intercept and send messages without control.
- Before sending offensive or spam messages, check if the victim's bank balance allows for recharging the mobile line..
- If the account has funds, Make a top-up and continue sending mass SMS to foreign numbers (which increases the telephone bill without the user noticing it until the end of the month).
- The content of SMS messages is often insulting, offensive, or designed to foster social distancing and blocking, adding a cyberbullying component.
- It spreads through fake apps, malicious links, and fraudulent updates.
SMSFactory: Invisible subscription to premium services and high-cost messaging
SMSFactory is another one highly dangerous Trojan which is wreaking havoc in Spanish-speaking countries and around the world. According to security labs, it works as follows:
- Reach the user through misleading advertising on low-reputation websites, promises of free services, game cheats, or adult content.
- By downloading the infected app (usually in APK format outside of Google Play), the user unknowingly enables the granting of dangerous permissions.
- The app is hidden in the system: It does not appear in the app drawer and its icon is not identifiable.
- The Trojan connects to remote servers, which tell it what commands to execute: send premium SMS, call high-cost numbers, subscribe the victim to paid services, etc.
- The user can accumulate tens of euros or dollars in monthly charges before realizing the fraud.
- In some cases, it copies the contact list to send messages to other people, facilitating the viral spread of malware.
Joker: Spyware and SMS Scams
Joker is the name given by Check Point to a family of spyware that, in addition to collect SMS messages, contact list, and device informationsubscribes users to paid SMS services without their permission. This family even infiltrates the Google Play Store using obfuscation techniques and disguises itself as messaging, health, utility, and other apps. Its rapid spread and difficult identification make Joker one of the most notorious mobile viruses of recent times.
How does malware that sends offensive messages spread?
Android malware propagation strategies have become increasingly ingenious:
- APK files downloaded outside of Google Play, especially from unknown websites, fake utility apps, mods of popular apps, or services that promise extra functionality.
- malicious links sent by SMS, WhatsApp, Telegram, email or social networks, sometimes from the account of an infected contact.
- Deceptive advertising and fraudulent ad networks that hide the installer in banners or pop-ups.
- Social engineering: Fake notifications of alleged prizes, job offers, or messages that appear to come from official agencies.
- Fraudulent updates, usually disguised as “security enhancements.”
Consequences and damages of a virus that sends offensive messages or spam
The negative effects of these viruses can be devastating and affect both financial and personal levels:
- High and unexpected billing for sending premium SMS, international SMS or SMS to unknown numbers.
- Mobile line blocking when billing limits are exceeded or the balance is exhausted.
- Loss of reputation If your contacts receive offensive messages or spam from your line.
- Theft of banking and personal data, data entry into fake apps and exposure to larger-scale fraud.
- Persistent vulnerability: The virus can install other types of malware (ransomware, spyware, banking Trojans, etc.) in the background.
- Battery and resource drain, system slowdowns and the appearance of intrusive ads.
Ways to detect an SMS malware infection on Android
Recognizing the presence of this type of malware as soon as possible is crucial. These are the most common signs:
- Atypical charges on your phone bill or unexplained out-of-balance notices.
- Complaints from your contacts who receive offensive or strange messages from your number.
- Unknown apps that appear in the list of apps, often hidden or without a visible icon.
- Unusual permissions requested by apps that do not need access to SMS, calls or contacts.
- Unusual device performance: Battery life is much shorter, the phone overheats, or intrusive ads and banners appear even on the lock screen.
- Suspicious activities in the bank account, such as repeated payments to unknown top-up platforms or services.
Real-life examples and documented cases of SMS attacks on Android
Reports from leading security labs highlight several specific cases of SMS attacks on Android, from which we can learn to prevent similar situations:
- Faketoken It came to control more than 5.000 smartphones simultaneously, sending thousands of offensive SMS to international numbers and draining associated bank accounts.
- SMSFactory It has wreaked havoc in Spain, France, the United States, Brazil, Argentina, and other countries, with users reporting up to $30 a month in undetectable charges until the end of the month.
- Joker and variants They have managed to bypass Google Play controls, infecting popular apps and spreading to hundreds of thousands of devices in a matter of weeks.
- Others Examples include Filecoder (ransomware spread via SMS), Emotet (banking Trojan), and smishing campaigns (SMS phishing) that steal bank and social media credentials.
Symptoms and warning signs: How to know if your Android is infected
The following are the most common warning signs that may indicate the presence of malware:
- The mobile phone gets hotter than usual or consumes excessive battery.
- Applications you don't remember installing or unknown icons.
- Pop-ups, ads, or strange notifications increase.
- Strange messages are coming to your contacts from your number or you receive automated messages to your own phone without explanation.
- The mobile phone bill rises unexpectedly or unauthorized payments appear.
- Apps crash, services fail, or your phone slows down significantly. even after reboot.
What to do if your Android is infected with a virus that sends offensive messages
- Disconnect your mobile from the Internet (Turn off Wi-Fi and mobile data). This will prevent the malware from continuing to send messages or spread.
- Review and remove suspicious applications- Go to Settings > Apps and uninstall any unknown apps. If it doesn't allow it, check the administrator permissions and remove them before deleting the app.
- Run an updated antivirus scanner from Google Play (such as Kaspersky, Avast, BitDefender, McAfee, or ESET). Remove any detected threats.
- Reboot the device in safe mode to prevent malicious apps from running while cleaning your system.
- Delete recently downloaded APK files from your downloads folder.
- Clear cache and browsing history in all installed browsers.
- Change all your passwords (banks, email, social networks) using a clean computer or a secure connection.
- If the problem persists, perform a factory reset. (Settings > System > Reset > Erase all data). Back up your important documents first.
- Contact your operator if high charges or problems with the line appear.
How to prevent infection: safety tips and best practices
- Download apps only from Google Play or official stores. Avoid APKs from unknown sources.
- Always disable the option to "Install apps from unknown sources" in the security settings.
- Always read the permissions that an app requests before accepting. Be wary if they ask for access to your SMS, calls, calendar, or device administrator without a reason.
- Don't click on suspicious links received by SMS, WhatsApp, email or social networks.
- Keep the operating system and all applications updated to have the latest security patches.
- Set up two-step verification for important accounts (email, banks, social networks, WhatsApp).
- Use a quality antivirus and keep it updated. There are free options on Google Play from reputable labs. Learn more at Do I really need an antivirus on my Android?.
- Check your phone bill regularly and consult your operator at the slightest sign of strange charges.
- Beware of public WiFi networks; use a VPN if you access sensitive services.
- Do not forward chain messages, sweepstakes, or suspicious promotions. circulating on WhatsApp or Telegram.
Types of SMS attacks and malware on Android: Beyond Faketoken and SMSFactory
SMS malware on Android can take many forms. The main types include:
- SMS Trojans: such as Faketoken, SMSFactory, which send messages, subscribe to premium services, spread viruses and steal data.
- Smishing: SMS phishing attacks impersonating banks, logistics companies, mobile operators, etc.
- Spyware and ransomware: They spy on conversations, record audio and video, encrypt files on the device, or demand a ransom.
- Adware: They display intrusive ads even on the lock screen, consuming resources and hindering normal mobile use.
- Clickers and ad fraud bots: They generate false clicks and can drain the battery quickly.
- Polymorphic viruses: They change shape periodically to avoid antivirus scanning.
Advanced malware detection and cleanup exercises
Frequent cases of scams and viruses via WhatsApp and SMS
Malware and instant messaging scams amplify the spread of the virus. Some common methods include:
- Links that promise gifts or giveaways: After clicking, you are asked to install an app outside of Google Play or provide banking details.
- Malicious files (GIF, PDF, Excel, APK) that when opened install the virus or steal information.
- Fake WhatsApp modifications or mods (WhatsApp Gold, WhatsApp Spy) that infect the device and display ads or steal data.
- Free Premium Account Offers (Spotify, Netflix, etc.) that lead to phishing or installation of Trojans.
- Phishing scams that impersonate WhatsApp technical support or request verification codes via SMS.
- Promises of free internet, WhatsApp color changes, fake coupons, and surveys that lead to fraudulent websites.
Recommended tools and apps to protect and remove viruses on Android
- Kaspersky Internet Security: Very effective in detecting SMS Trojans and spyware.
- Avast Mobile Security: Provides automatic scanning and threat cleanup.
- Malwarebytes: Useful for removing adware, trojans and resistant viruses.
- ESET Mobile Security: stands out for its real-time analysis and protection against premium SMS.
- BitDefender Mobile Security: great relationship between resource consumption and protection.
- NetGuard: Allows you to block suspicious outgoing connections.
- Glasswire: Monitors traffic and alerts of unusual activities.
Frequently Asked Questions About the Android Virus That Sends Offensive Messages
- Can the virus be removed by restoring the device? In most cases, yes. A factory reset usually removes malware, but You must back up your data beforehand.
- Can I get infected just by opening an SMS? Generally, you'll need to install an app or grant permissions. But don't click on links or download files without verifying their source.
- Are there viruses that affect iPhone? Although Android is the most affected platform, there are threats to iOS. The best defense is to update your system and avoid installing profiles or apps from unverified sources.
- Is Google Play Protect antivirus enough? It's a good first filter, but it doesn't detect all modern variants. Always complement it with a recognized antivirus.
Extra protection and prevention tips
- Avoid pirated or "free" apps from third-party sourcesThey usually hide viruses or adware.
- Be wary of banners and ads on disreputable websites.
- Change your passwords frequently and use professional password managers.
- Educates older and younger people about the risks of installing unknown apps or forwarding suspicious messages.
- Disable automatic download of media files in WhatsApp to prevent harmful files from being installed without your consent.
How to proceed if you are a victim of a scam or infection
- Notify your contacts do not open messages or links sent from your mobile.
- Contact your operator if you see improper charges or problems with the line.
- Report the incident to cybersecurity agencies or the police to prevent the spread and provide legal assistance to others affected.
- Use the "Report" or "Block" tools on WhatsApp and other apps to limit dissemination.
- Eliminates any trace of the virus before using your phone normally again.
The Future of Android Viruses: Trends and Recommendations
The rise of SMS threats and sophisticated Trojans shows that Mobile security is more important than everWith the growth of banking, messaging, and online shopping apps, our mobile phones are now the preferred gateway for cybercriminals. Trends indicate that viruses will become increasingly complex, automated, and difficult to identify with the naked eye. Therefore, it's best to stay ahead of the curve, apply good practices, and never let your guard down.
Digital education and common sense remain the most effective barriers against malware. An educated user who reviews permissions, distrusts anything that's "too good to be true," and keeps their phone up-to-date and protected will always be a very difficult target for attackers.
The proliferation of Android viruses that send offensive messages is a real and growing problem. With the methods, tips, and tools described in this article, you can protect your device and your privacy, detect any threats in time, and avoid unpleasant surprises on your bill or your digital reputation. Stay alert and enjoy technology with peace of mind.