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Taiwan Businesses Targeted by Winos 4.0 Malware

malicious emails, National Taxation Bureau, Ophtek, Phishing, Silver Fox, Taiwan, Win 4.0malicious emails, National Taxation Bureau, Ophtek, phishing, Silver Fox, Taiwan, updates, Winos 4.0Ophtek, LLC

Apr 2025

A recent cyberattack has targeted Taiwanese companies using phishing emails which appear to be from Taiwan’s National Taxation Bureau.

In this attack, cybercriminals sent phishing emails to businesses in Taiwan, pretending to be officials from the National Taxation Bureau. These emails contained malicious attachments designed to infect victims’ computers with malware. The threat actors’ aim was to steal sensitive information and gain unauthorized access to IT infrastructures, enabling the attackers to have easy access to secure data.

How Did the Winos Attack Unfold?

The threat actors created emails which, at a quick glance, appeared official and claimed to provide a list of companies scheduled for tax inspections. The recipients were urged to download a zip file containing this list. However, contained within this ZIP file was a dangerous DLL file named lastbld2Base.dll. Once this file was activated, it set in motion a series of malicious actions – the most prominent of which was to download the Winos 4.0 malware. Winos 4.0 allowed the threat actors to take screenshots, record keystrokes, and remotely execute commands on the infected devices.

Once installed, Winos 4.0 gave the attackers deep access to the compromised systems. This access made the malware a powerful tool for carrying out espionage, especially given that the main targets appeared to be corporate businesses. These types of targets allowed the threat actors to gain access to huge amounts of personal data, rather than targeting individuals one at a time to harvest such data.

Security researchers believe that a hacking group known as Silver Fox are the perpetrators behind the attack. Silver Fox has a history of targeting Chinese-speaking users and has previously been observed using fake software installers and malicious game optimization apps to deceive victims.

Protecting Yourself from Such Attacks

This incident is further evidence that phishing campaigns are becoming more deceptive and underlining the importance of social engineering tactics for hackers. Many people glance over their emails quickly and, if they see an official and trusted government logo, the chances are that they’ll believe it’s genuine. However, it’s important that you and your employees stay safe, so make sure you practice the following:

Be Careful with Email Attachments: Always double check the authenticity of and email before downloading or opening email attachments, especially if they are unexpected or urge you to perform a specific action. If an email claims, for example, to be from a government agency, visit the official website to confirm its legitimacy before opening any attachments.
Keep Software Updated: Regularly updating your operating system and security software is crucial for protecting your PCs against known vulnerabilities. Many cyberattacks take advantage of outdated software with numerous vulnerabilities, so keeping your system up to date should be a priority at all times.
Educate Employees: Ensuring that your staff can recognize phishing attempts is crucial in 2025, as is carrying out safe email practices to prevent accidental exposure to malware or malicious links. Implementing cybersecurity awareness programs should be a priority for your IT inductions. Regular refresher courses should also be to help consolidate this learning.

For more ways to secure and optimize your business technology, contact your local IT professionals.

Google Ads Used to Push Fake Google Chrome Installer

google ads, Google Chrome, malware, Ophtek, SecTopRat, security software, security_updateschrome, Google ads, malware, Ophtek, SecTopRat, security, updatesOphtek, LLC

Mar 2025

Cybercriminals are exploiting Google Ads to distribute malware disguised as a genuine Google Chrome installer, tricking users into downloading the malware.

Threat actors are always innovative, and this recent attack underlines exactly why you need to be on your guard when online. Attackers have been purchasing ads which appear when PC users search for popular software downloads e.g. Google Chrome. Unfortunately, the ads which are served up lead to dangerous websites which closely resemble official download pages. This deception tricks users into downloading and installing malware.

As we spend a high proportion of our work time online, we’re going to dig deep into this attack to see what we can learn.

How Can Google Ads Compromise Your PC?

In this attack, users searching with terms such as “download Google Chrome” might find themselves confronted with a sponsored ad at the top of their search results. This ad can, at first, appear genuine, often having a URL which includes “sites.google.com” – a Google platform used to build free websites. Accordingly, users feel confident that these pages are official and trustworthy, especially when they look very similar to official download sites.

Once a user clicks the ad, they’re redirected to a malicious page which is a highly convincing imitation of the official Google Chrome download site. This page urges users to download a file named “GoogleChrome.exe” and, so far, everything appears as you would expect. With nothing unusual to suspect, users make the decision to trust the page, download the file, and then launch it.

However, once executed, the installer begins to act suspiciously. Firstly, it connects to a remote server to retrieve additional instructions. Secondly, it requests that they user grants it administrative privileges to assist in completing the download. At this point, alarm bells should start ringing, but most users still feel as though the software can be trusted. Once administrative privileges are granted, the installer executes a PowerShell command which prevents Windows Defender from scanning the malware’s location, enabling it to operate quietly in the background.

A further file is then downloaded to the BackupWin directory and, masquerading under the name of a genuine piece of software, opens up a communication channel with the threat actors’ remote server. The malware used is SecTopRAT, a Remote Access Trojan which allows the attackers to take remote control of the infected system and steal sensitive data such as capturing keystrokes, accessing files, and recording user activities.

Protecting Against the SecTopRAT Threat

Your employees are busy with their daily tasks and, therefore, it’s easy for them to have a lapse of judgement and quickly click on something they believe to be genuine. However, this can be disastrous for your IT infrastructure, so it’s crucial that your staff are mindful of the following:

Be Cautious of Sponsored Ads: Just because an ad is that the top of the search results, this doesn’t mean it can be trusted. This is why it’s important to always verify the authenticity of a URL before clicking it. Check for any unusual spellings or, to be fully safe, navigate directly to the official website for that software.
Only Download from Official Sources: The best approach is to always head straight to the developers website rather than trusting other online sources. Aside from sponsored ads, it’s critical that your team avoids downloading via links in emails or through torrent sites – both of these sources often lead to nothing but malware.
Keep Your Security Software Updates: One of the simplest ways to thwart attackers is to make sure your security software is up to date. This software regularly scans your system for threats, but it needs to be updated as soon as possible to detect the latest threats.

For more ways to secure and optimize your business technology, contact your local IT professionals.

Malicious Code Found Embedded in Steam Downloads

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Mar 2025

A malicious game on Steam called PirateFi was found to contain malware which steals personal information, highlighting the risks of unverified downloads.

A recent attack involving a game on Steam has highlighted the importance of vigilance when downloading software. The game, called PirateFi, was available to download on Steam – an online platform for buying and playing games – but contained malware designed to steal personal data from players’ computers.

Pirates Strike Gold on Infected Systems

PirateFi – which was a free to play game – was developed by Seaworth Interactive and available on Steam from February 6th to February 12th, 2025. Promising an engaging and challenging survival experience, setting players objectives such as base building, food gathering, and making weapons, PirateFi was downloaded by around 1500 players and generated numerous positive reviews.

However, it was soon discovered that PirateFi was not simply a game meant to excite players and take their minds off the real world. Reports soon emerged that the game contained malware known as Vidar, a data-stealing program. Vidar is designed to harvest sensitive data from infected computers, so this could easily include passwords, financial information, and personal documents. Rather than Vidar being bundled with PirateFi as bloatware, Vidar was embedded within the game’s files, allowing it to be launched when the game was started.

Valve, the company behind Steam, quickly removed PirateFi from their platform on February 12^th, when the threat was identified. They were also swift in issuing security notifications to those who had downloaded the game. Valve’s advice was, for those who had downloaded PirateFi, to run a full system scan using up-to-date antimalware software to detect and remove any dangerous files. Alternatively, Valve suggested that those at risk fully reinstalled their operation system to ensure Vidar was completely removed.

Staying Safe from Dangerous Downloads

This attack underlines the ingenuity and evolving tactics of threat actors, who are increasingly targeting popular platforms like Steam and GitHub to distribute their malware.

By disguising their malware as legitimate tools on these platforms, the threat actors are exploiting the trust users place in these websites. For a threat actor, this is fantastic as it opens up their attack to a huge audience. However, for a user it’s highly frustrating and dangerous. Accordingly, you need to practice the following to remain safe:

Be Cautious with Unverified Software: Before downloading and installing new software, especially from lesser-known sources, always take the time to research the application. Seek out reviews from reputable sources and check for any reports of malicious activity relating to the software.
Keep Your Security Software Updated: Ensure that your antivirus and anti-malware programs are always up to date. Regularly scan your system for potential threats, particularly after installing new applications. Updated security software can detect, quarantine and delete the latest malware threats before they can take hold of your system.
Monitor for Unusual Activity: Always be mindful of any suspicious activity on your networks, such as unusual drops in performance, unfamiliar programs executing, or unauthorized access to your accounts. If you notice signs such as these, there’s a chance that your network has been breached.

For more ways to secure and optimize your business technology, contact your local IT professionals.

In a shock move, U.S. Defense Secretary Pete Hegseth has ordered Cyber Command to stop all cyber operations against Russia.

The Shift in Policy

On February 28^th 2025, Secretary of Defense Pete Hegseth issued a directive ordering US Cyber Command to immediately call off all offensive cyber operations which target Russia. This order was communicated directly to Cyber Command’s leader, Gen. Timothy Haugh, who then instructed his teams to stand down. It was a decision which reportedly took many within the Department of Defense by surprise. Many ongoing cyber operations against Russian state-sponsored hacking groups had been in progress for some time, so the increased risk of cyberattacks was a major concern.

Established in 2010, Cyber Command has played a key role in US cybersecurity strategy for 15 years. From protecting cyberspace through to disrupting Russian cyber threats and state-backed hacking campaigns, Cyber Command has played a major role in preventing attacks which have targeted government infrastructures and private companies. It’s important to note, however, that while Cyber Command’s operations against Russia have been put on hold, other US intelligence agencies are still permitted to monitor and collect information on Russian activities online.

Why Were US Cyber Operations Stopped?

Hegseth’s directive has caused equal measures of concern and intrigue. It was a move which no one saw coming and the objectives remain unconfirmed. The main reason behind the decision appears to be a shift in foreign policy by the new administration. President Donald Trump has long been open about his desire to build diplomatic bridges with Russia, which have been tense since Moscow’s 2022 invasion of Ukraine. Trump has promised his electorate he will put a swift end to the war in Ukraine but appears to be taking the side of Russia by blaming the conflict on Ukraine.

Many suspect that, by ending cyber operations against Russia, the US administration aims to demonstrate an end to hostilities between the two nations, with the Kremlin benefitting significantly from this act of goodwill. Nonetheless, many critics are arguing that this move weakens the defenses of the US and encourages Russia to continue its cyberattacks without consequence.

Is US Cybersecurity Now at Risk?

The ramifications of this controversial decision have the potential to be far-reaching. National security has long relied on cyber strategies and operations to protect US interests. Russian cyberattacks have been plentiful in recent years, with 2024 seeing Russian hackers striking critical US infrastructures. Accordingly, the ongoing presence of Cyber Command has been crucial in countering Russian attacks in the digital landscape. Experts fear that suspending these activities could have several consequences:

Increased Russian Cyber Threats: Initiating offensive cyber operations helps to neutralize Russian hacking groups by disrupting their networks and exposing their tools. With these interventions now halted, hacking groups will be able to relax and operate more freely.
Weakened Infrastructure Defenses: Almost all major infrastructures within the US rely on digital access, putting them at risk of external threats. Therefore, with their cyber defenses weakened, power grids, financial institutions, and government agencies are all at an enhanced risk of foreign attacks.
Impact on Ukraine and NATO Allies: The US has, until now, been providing valuable cyber assistance to Ukraine and its NATO allies. This has helped them defend against Russian cyberattacks and minimize damage. But this policy change will undoubtedly reduce support, leaving allies more exposed to cyberattacks.
Potential Future Implications: By relaxing cybersecurity efforts against Russia, the US could easily be seen as going light on Russia’s aggressive cyber activity. Russia, meanwhile, could perceives this as a sign of US weakness and take advantage by increasing their cyber activities against the US government.

What Has the Reaction from the Digital Community Been?

Understandably, this news story has caused major debate amongst politicians, journalists and commentators in the digital community. Strong opinions have been voiced, and the internet has been ablaze with polarizing comments.

Lawmakers from Congress have criticized the decision and compared it to removing the military’s ability to defend itself against aggressive action in war. At the same time, cybersecurity experts have condemned the move and pointed at the obvious fact that Russia now has free rein to target critical infrastructure in the US. Commentators on Reddit have been much harsher, with conspiracy theories swirling that Russian executives have infiltrated the Trump administration.

The Immediate Future of US Cybersecurity and Russia

For now, Cyber Command is following orders and has ceased its offensive operations. However, it remains unclear whether this is a temporary move or part of a long-term strategy. If Russian cyber activity increases significantly, surely there will be a change in policy. Only time will tell.

For more ways to secure and optimize your business technology, contact your local IT professionals.

Vulnerable ASP.NET Keys Used to Unlock PC Security

ASP.NET keys, malicious code, malicious ViewState, Microsoft, monitor applications, Ophtek, System UpdatesASP.NET Keys, malicious code, malicious ViewState, microsoft, Monitor Applications, Ophtek, system updatesOphtek, LLC

Mar 2025

Attackers are exploiting exposed ASP.NET keys to inject malicious code into web applications, leading to unauthorized access and potential data breaches.

Microsoft has announced that a major security issue has been identified where cybercriminals are taking advantage of publicly available ASP.NET machine keys. These keys, usually used to secure web applications, are being altered to insert harmful code, compromising the security of affected systems.

What is ASP.NET and How Does it Work?

ASP.NET is a free framework developed by Microsoft to help people build web applications and services. Part of this framework involves a feature called ViewState, used to help web pages remember user data and maintain this information across different sessions. To protect this data, ASP.NET uses machine keys such as ‘validationKey’ and ‘decryptionKey’ to ward off any malicious activities. These keys are used to encrypt and validate the data, ensuring it remains secure and confidential.

However, an investigation by Microsoft’s Threat Intelligence team has discovered that some developers are copying these machine keys from online sources, such as repositories, and using them in their own applications. This practice quickly becomes a risk when the same keys are reused across multiple applications or when they can easily be found. These scenarios allow threat actors to find these keys and use them to create malicious versions of ViewState data.

How has ViewState Been Compromised?

When a threat actor gets hold of a machine key used by a target application, they can create a malicious ViewState – this is a piece of data typically trusted by the application and won’t ring any alarm bells. The malicious ViewState is sent to the server through a POST request. As the ViewState is signed with the correct machine key, the receiving server believes it’s genuine. Once this data has been received and processed, the server unknowingly executes the malicious code embedded within the ViewState.

This method grants threat actors remote access to the compromised server and free rein to execute any processes they want. So, for example, the threat actors could download additional malware, steal sensitive information, and take full control of the server. In one case, the attackers used this technique to launch a cryptocurrency miner on a compromised server. This allowed the threat actors to take control of any PCs on the infected server and use their resources to generate digital currencies. This may sound harmless but it’s at the expense of the PCs performance.

Protecting Yourself from Malicious ViewState

ASP.NET is highly popular and is used by countless websites, so it’s important that we understand the best way to protect users of the framework. Here’s Ophtek’s three top tips for safe usage of ASP.NET:

Use Unique and Secure Keys: Developers using ASP.NET should generate unique machine keys for each application. Always avoid copying keys from online sources or reusing them in other applications. This practice ensures that even if one application’s key is compromised, others remain secure.
Regularly Update Systems: It’s paramount that, as with all software, your web applications and servers are up to date with the latest security patches. Regular updates help you address zero-day vulnerabilities and reduce the risk of your IT infrastructure being compromised.
Monitor Application Activity: You should always use monitoring tools to keep an eye on application behavior. Unusual activities, such as unexpected POST requests or unauthorized installs, can be early indicators of a developing attack. By conducting regular audits, you can increase your chances of stopping an infection before it causes damage.

For more ways to secure and optimize your business technology, contact your local IT professionals.

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