Yellow Trojans are a type of malware that infects computers and other devices. The name comes from the Trojan Horse in Greek mythology, as this malware often disguises itself as legitimate software to trick users into downloading and installing it. Once installed, yellow Trojans can cause a variety of problems, from showing annoying ads to stealing personal information.
What is malware?
Malware is short for “malicious software.” It is any program or code that is designed to cause damage, access private information without consent, or otherwise disrupt normal operations. Malware comes in many forms, including viruses, worms, spyware, ransomware, and Trojans.
Viruses and worms are able to self-replicate and spread themselves automatically once they have infected a system. Spyware gathers data and personal information covertly. Ransomware encrypts files and data on a device until a ransom is paid.
Trojans disguise themselves as legitimate applications to trick users into installing them. Once installed, they carry out malicious activities in the background without the user’s knowledge.
How yellow Trojans operate
Yellow Trojans get their name from the yellow background they often display on infected computers. Their operations can include:
– Installing additional malware programs on the infected device to expand the attack.
– Logging keystrokes to steal login credentials, financial information, and other sensitive data.
– Hijacking system resources to mine cryptocurrency using the infected computer’s processing power.
– Opening backdoors that allow remote access and control over the infected system.
– Downloading and installing software updates without the user’s consent or knowledge.
– Bombarding the user with intrusive pop-up ads.
– Redirecting internet traffic through malicious proxies for surveillance purposes.
– Crashing processes and applications, causing system instability.
The term “yellow” refers to the fact that many yellow Trojans change the computer’s background screen to a yellow color after infecting it. This is done to signal to the attackers that the malware is active and operating on the system.
How are yellow Trojans distributed?
Yellow Trojans use several distribution methods to spread and infect new devices:
– **Bundled with freeware software downloads** – The Trojan file is included as part of a free program bundle. If the user installs the freeware, the Trojan is installed at the same time without their knowledge.
– **Fake software updates** – Pop-ups may appear claiming a critical update is available for Flash Player, Java, or other common applications. If the user clicks to install it, the update file actually contains a Trojan.
– **Email attachments** – The Trojan file is attached to spam emails disguised as invoices, delivery notices, or other files that appear legitimate. Just opening the attachment triggers the infection.
– **Malicious links** – Links to the Trojan file are spread on social media, messaging apps, questionable websites, and other locations. Clicking the link downloads and installs the malware.
– **Infected removable drives** – USB flash drives containing the Trojan file are left in public places, hoping victims will pick them up and insert them into their computers.
Signs of a yellow Trojan infection
Here are some signs that may indicate a yellow Trojan infection:
– Computer background turns yellow. This is the most obvious sign of a yellow Trojan.
– Sudden system crashes and freezes become frequent.
– Strange new toolbars appear in web browsers.
– You are redirected to unknown web pages against your will.
– New programs appear that you did not install.
– Computer runs much slower even though you have not installed or downloaded anything.
– Pop-up ads begin appearing frequently.
– Friends receive spam emails from your email account without your knowledge.
– Antivirus program will not start or update, or it disappears completely.
– Files become corrupted or encrypted without explanation.
If you observe any of these symptoms, your system may be infected with a yellow Trojan or other malware.
How to prevent yellow Trojan infections
Here are some tips to avoid yellow Trojans and stay protected:
– Use trustworthy antivirus software and keep it updated. This will detect and block known Trojans.
– Avoid clicking links or attachments in unsolicited emails. Check the source before opening.
– Only download software from official sources like app stores. Avoid sketchy freeware.
– Make sure all your applications and operating systems are updated. Updates fix security flaws.
– Turn off auto-run features that open flash drives and CDs automatically. Only open them when you choose to.
– Be wary of free Wi-Fi hotspots. They are common places to get infected. Use a VPN when connecting.
– Don’t click on pop-up ads or notifications urging you to scan your system. These are often fake alerts.
– Use ad blockers in your web browser to avoid malicious ads.
Practicing caution online and keeping security software up to date will help prevent yellow Trojans from infecting your devices.
How to remove a yellow Trojan
If your system does get infected with a yellow Trojan, here are steps to remove it:
1. **Disconnect from the internet** – Unplug your internet connection or disable your Wi-Fi. This stops the Trojan from communicating.
2. **Boot into Safe Mode** – Restart your computer and boot into Safe Mode. This prevents the Trojan from loading.
3. **Scan with antivirus software** – Run a full system scan. Quarantine anything detected, especially the yellow Trojan files.
4. **Delete associated files** – Remove any unfamiliar programs, toolbars, and files that appeared. Also clear temporary files and caches.
5. **Reset browser settings** – Open web browsers and reset them to default settings. This undoes any unwanted changes made by the Trojan.
6. **Change all passwords** – Once the system is clean, change passwords for all accounts accessed from that device.
7. **Install security updates** – Make sure to update your operating system, software, antivirus, and firewall after removing the Trojan.
8. **Run regular scans** – Continue running periodic antivirus scans to catch any remnants of the infection.
With vigilance and using proper security tools, you can both avoid yellow Trojan infections and remove them if they do occur. Keep your software updated and be wary of suspicious links, pop-ups, and attachments.
Types of yellow Trojans
There are many variants of the yellow Trojan malware. Some of the major types include:
– **PWS:Win32/Fareit** – One of the most common yellow Trojans. It steals financial data and redirects web traffic for profit.
– **Trojan.Starter.YY** – Displays pornographic pop-up ads. It blocks security scanners to avoid detection.
– **Win32.Sality** – Spreads quickly through network shares and removable drives. It also disables antivirus software.
– **Trojan.Banker** – Designed specifically to steal banking and financial account credentials via keylogging and form grabbing.
– **Ransom.Cerber** – Encrypts documents and photos while displaying a ransom note over a yellow background.
– **Backdoor.Win32.Poison** – Creates a backdoor to give attackers full remote access and control over the system.
– **Trojan.Danabot** – Downloads additional malware payloads. It also records audio, copies keystrokes, and takes screenshots.
– **Trojan.Fakeav** – Pretends to be antivirus software and produces fake scan results in order to trick the user into paying to remove non-existent infections.
These examples demonstrate the wide range of malicious activities that yellow Trojans can carry out. Keeping antivirus software updated is key to stopping them.
The history of yellow Trojans
Yellow Trojans first emerged in the early 2000s along with the growth of internet access and online commerce. Some key events in the history of yellow Trojans include:
– **2001** – Gpcode, one of the first yellow Trojans, spreads via email and disables antivirus software. It was difficult to remove.
– **2003** – Serious yellow Trojans like PSW.Win32.Poison begin appearing. They have rootkit capabilities to hide deep in systems.
– **2007** – The Win32/Fareit Trojan steals users’ financial data from browsers during online banking sessions.
– **2010** – Trojan.Danabot emerges as a highly advanced threat, stealing passwords and recording audio/video.
– **2013** – The creative Trojan.Ransom displays a ransom message over a yellow background instead of encrypting files.
– **2016** – Cerber ransomware adds the yellow background technique to encrypt thousands of victim’s files.
– **2020** – Modern yellow Trojans like Trojan.Starter.YY use TikTok and social media to spread.
As long as money can be made through scams, extortion, and theft, yellow Trojans and their creators will continue to evolve and find new ways to infect computers and mobile devices.
Advanced capabilities of modern yellow Trojans
Yellow Trojans today have some dangerous capabilities that make them more crafty and difficult to detect. These include:
– **Code obfuscation** – Scrambling their code so antivirus engines cannot analyze it.
– **Using legitimate sysadmin tools** – Like PowerShell and Windows Management Instrumentation for infection routines.
– **Disabling security software** – Preventing antivirus programs and firewalls from updating and operating properly.
– **Resisting removal** – Embedding themselves deep in registries, directories, and other system areas.
– **Active evasion** – Detecting sandbox and analysis environments and masking malicious behavior.
– **Spreading via proxies** – Using hijacked computers and devices as proxies to hide the source.
– **Targeted social engineering** – Crafting attacks that appeal to the victim’s interests and connections.
– **Mutating constantly** – Modifying code and files enough to avoid signature detections.
– **Mining cryptocurrency** – Using victims’ CPU and GPU power to mine Bitcoin and other digital currencies.
With these sneaky capabilities, modern yellow Trojans can infect systems while avoiding security measures. Users must be extra cautious when downloading files and clicking links online.
Future outlook and projections
Yellow Trojans show no signs of disappearing anytime soon. Here are some projections for the future threat landscape:
– Attacks on cloud environments will rise as more data and infrastructure moves online. Cloud malware is more difficult to detect.
– More Trojans will leverage AI to analyze systems, adapt to defenses, and launch smarter social engineering.
– Mobile Trojans will explode in popularity as users depend on phones and tablets for more computing and finances.
– IoT devices from watches to appliances to cars will become vulnerable to yellow Trojan attacks.
– Disablement of security software will remain a top focus to allow deeper system infiltration.
– Cryptocurrency miners embedded in Trojans will be a constant background threat on many systems.
– Highly targeted attacks on healthcare, government, and infrastructure will have dire impacts.
Ultimately, the distributed, constantly adapting nature of yellow Trojans means the threat can never be eliminated entirely. But with vigilance, proper security software, and safe online practices, the damage can be limited.
Conclusion
Yellow Trojans have tormented internet users for over two decades and continue to evolve. Their primary attractions to attackers are money and control. By compromising computers with stealthy, disguised malware, they can disable security measures, steal personal data, demand ransoms, or harness computing resources. While many variants exist, they share the hallmarks of deceiving victims into installing them, changing the system’s appearance, damaging performance, accessing private data, and spreading to other devices. With common sense online and cutting-edge cybersecurity tools, individuals and organizations can identify and remove yellow Trojans before they cause too much damage. But these threats should never be taken lightly in our increasingly digital and connected world.
