How to remove Trojan:Win32/Bluteal.B!rfn

Trojan:Win32/Bluteal.B!rfn – a false positive by Windows Defender, although users should not let their guard down

Trojan:Win32/Bluteal.B!rfn might be a malicious application that infected your machine without you noticing, such as a trojan horse or a crypto miner^[1] (this malicious software became quite popular among cybercriminals recently). Microsoft forums were flooded with questions, as users reported that Windows Defender is also detecting files of legitimate programs as malicious. Although Microsoft confirmed that it might be a false positive in some cases, it can also indicate a severe computer infection.

False positives happen from time to time to every single AV engine, and it is due the code particular programs are written in. Users can report certain detections as false positives so that security researchers could investigate further. Additionally, users can also set the detected program as an exception, if they are entirely sure that it is not malware.

Nevertheless, we do not recommend doing that, especially if you are not that computer-savvy. In some cases, the detection might be real – Trojan:Win32/Bluteal.B!rfn removal would be required. If you are not sure if the detected file is actually malicious, you should scan your computer with FortectIntego, SpyHunterCombo Cleaner or other security software that could confirm that the file is indeed malicious.

Users also reported that even Windows files could be flagged as a BluTeal trojan, such as Microsoft.CertificateServices.PKIClient.Cmdlets.ni.dll or Microsoft.VisualStudio.Utilities.Internal.ni.dll. These reports started to occur at around May when it was added to Windows Defender. The description of the threat seems to be not quite definite:^[2]

This threat can perform a number of actions of a malicious hacker's choice on your PC.

However, according to Microsoft's definition version 1.271.37.0, an update has been made to the Trojan:Win32/Bluteal.B!rfn, and possibly removed the change of it being a false positive. Nevertheless, there is no official confirmation that is has been fixed yet, and users might have to wait for the next Windows Defender update. Still, security experts^[3] recommend to keep security software up to date – make sure the version of your security software is the latest one.

As of now, we advise you not to rush if your anti-virus detected a trojan. It might be a false positive, and it might be not. If the latter is true, you would have to remove Trojan:Win32/Bluteal.B!rfn virus from your machine carefully, especially if your computer is experiencing error messages, BSoDs, slowdowns, high CPU/GPU usage, increased amounts of ads, and similar behavior. 

Trojan horses can be avoided by being careful online

False positives may confuse users, as they might see a legitimate program being flagged as malicious. However, security experts recommend always to take a great interest if the AV engine flagged something. It can still be a virus which can significantly damage your computer or steal personal data. Therefore, it is vital to be careful online. Even though nothing can make you secure from viruses 100% but there is still something you can do to lessen the chance of infection:

• install anti-malware software – that is the basic rule which can save you hundreds of dollars and your precious files;
• back-up your data on a remote server or an external HDD;
• avoid visiting websites of dubious content, such as free online gaming, adult, file-sharing, gambling, etc.;
• do not download software or its updates from third-party sites;
• do not click on the suspicious spam emails – phishing emails is the most prominent malware distribution method;
• patch your operating system and software regularly;

Make sure you remove Trojan:Win32/Bluteal.B!rfn if it is malicious

Regardless if Trojan:Win32/Bluteal.B!rfn is a virus or not, we recommend users to investigate further, and opt to scan their machines using additional reputable security software – FortectIntego or SpyHunterCombo Cleaner. In some cases, malware can be hard to detect and not all anti-virus tools are capable of doing that.

If the file is indeed malicious, do not delay Trojan:Win32/Bluteal.B!rfn removal. Do not even try eliminating the cyber threat manually, as this action can only be performed successfully by IT experts. Trojans and similar infections have a complicated code which modifies system files, and it is hard to set everything back to normal without the anti-virus tool.

If you struggle to remove Trojan:Win32/Bluteal.B!rfn virus, you should reboot your Windows machine and enter Safe Mode with Networking, as explained below.