How to remove CStealer Chrome Trojan

This article elucidates the emerging scourge of the CStealer Chrome Trojan and provides easy-to-follow steps to detect and remove this info-stealing threat.

1. What is CStealer Chrome Trojan?
2. Automated removal of CStealer Chrome Trojan
3. Restore web browser settings to their original defaults

What is CStealer Chrome Trojan?

Cybercriminals have recently synthesized a brand-new flavor of malicious reconnaissance. It is laced into a Trojan infection codenamed CStealer. First spotted in November 2019, this threat inspects Google Chrome browser for usernames and passwords the victim previously chose to save as part of simplifying their login routine. On a side note, everyone is familiar with prompts generated by modern browsers once the user has typed in their credentials to access an arbitrary personal web account. These dialogs ask whether or not these sensitive details should be saved so that there is no need to re-enter them manually the next time. Obviously enough, this data is stored in the current browser set-up. The CStealer Trojan zeroes in on the login information Chrome retains within the default path allocated for this particular purpose. It knows where to look, and what’s worse, how to perform exfiltration of the wrongfully extracted authentication values to its operators.

Whilst this is far from being a new tactic in this domain of electronic crime, the malicious actors who masterminded CStealer have equipped their contrivance with an unprecedented feature. It comes down to a unique way of submitting the collected confidential info to the crooks in charge. The Trojan establishes a covert connection with a MongoDB server and instantly sends all of the prey’s usernames and passwords it can pilfer in Chrome. To access this C2 entity holding the entire sketchy database, the pest leverages credentials integrated into its code. The server communication is deployed via what’s called “libmongoc”, the MongoDB C Driver client library which features a cross-platform compatibility. This technique expands the potential attack surface and ensures that the surreptitious data transmission process is seamless.

The malefactors behind this ongoing campaign can therefore get hold of the constantly updated database of stolen info whenever they want. All it takes is authenticating with the MongoDB server in question. From there, the data can be abused in multiple different ways. One of the likely scenarios is that the hackers can perpetrate Internet banking frauds by impersonating the victims and initiating financial transactions in their name. In this case, the felons are a few mouse clicks away from getting incoming money transfers from the plagued users’ bank accounts. Identify theft is another adverse consequence or exploitation enabled by CStealer Chrome Trojan. Furthermore, the black hats may be able to carry out highly plausible phishing attacks where the recipients open harmful email attachments or hand over their secrets without a second thought.

CStealer is undoubtedly one of a kind when it comes to its authors’ TTPs (tactics, techniques, and procedures), but its distribution is quite prosaic. The primary infection vector is malicious spam generated through the use of a botnet. Having discovered a regular-looking invoice, notice from a service provider, or other document attached to a new message in the inbox, unwitting users might get curious to see what’s inside and open the embedded file. At this point, they have no idea that the bait has been taken and the malware infiltration chain is a matter of clicking another innocuous-looking button to enable macros or run an executable disguised as something entirely benign.

One more mechanism of CStealer distribution capitalizes on freeware bundles that promote the harmful code alongside some trustworthy application. The mix of reported propagation channels additionally includes P2P sharing networks such as BitTorrent, as well as keygen programs claiming to activate pirated copies of legit software. No matter how exactly this password-stealing Trojan has snuck into a computer, the sooner it is detected and removed – the better. Here are some worthwhile tips to get rid of it.

Automated removal of CStealer Chrome Trojan

Owing to an up-to-date database of malware signatures and intelligent behavioral detection, the recommended software can quickly locate the infection, eradicate it and remediate all harmful changes. So go ahead and do the following:

1. Download and install the antimalware tool. Open the solution and have it check your PC for PUPs and other types of malicious software by clicking the Start Computer Scan button

Download CStealer Trojan remover

2. Rest assured the scan report will list all items that may harm your operating system. Select the detected entries and click Fix Threats to get the troubleshooting completed.

Use Control Panel to get rid of the CStealer virus

• Open up the Control Panel from your Start menu in Windows. Open up the Control Panel from your Start menu in Windows. Depending on the OS build, select Uninstall a program (Windows 10, 7 and Vista) or Add or Remove Programs (Windows 8)
  
• To facilitate the process of locating the threat, sort the programs list by date to get the latest ones displayed at the very top. Find an unfamiliar, suspicious entry under the Name column, click Uninstall and follow further directions to get the removal done

Restore web browser settings to their original defaults

In the circumstances of a complex browser hijack like this, executing a reset makes the most sense despite a few obvious downsides. Customizations such as saved passwords, bookmarked pages etc. will be gone, but so will all the changes made by the potentially unwanted program. The instructions below address the workflow for the web browsers most targeted by the CStealer Trojan.

Reset Google Chrome

• Open Chrome, click the icon for Chrome menu and choose Settings
  
• Scroll down the settings screen and click Show advanced settings
  
• Click Reset settings
  
• Finally, confirm the restoration by clicking Reset on the warning message
  
• Restart Chrome

Reset Mozilla Firefox

• Open Firefox, type about:support in the URL area and press Enter
  
• On the Troubleshooting Information screen, spot the Refresh Firefox button and click on it
  
• Follow subsequent directions to reset Firefox to its original settings
  
• Restart the browser.

Reset Internet Explorer

• Select Internet options under IE’s Tools (Alt+X)
  
• Proceed by clicking on Advanced tab, then select Reset
  
• To confirm the intended changes, click Reset on the Reset Internet Explorer Settings screen after ascertaining that the Delete personal settings checkbox is enabled
  
• Reboot the machine to fully implement the fix.

Reset Safari

• Go to the Safari menu and select Preferences
  
• When on the Preferences screen, select the Privacy tab and hit the Remove All Website Data button if you are up to erasing all website data stored on your Mac. Otherwise, you can use a site-specific removal option described below
  
• A dialog will appear, asking you to validate your choice. Click the Remove Now button if you are sure. Be advised this will log you out of online services and undo personalized web browser settings such as saved passwords, etc.
  
• Safari also allows deleting data for specific sites rather than all sites in general. To use this option, click the Details button under Privacy tab
  
• Select the websites for which you would like to erase data and click the Remove button
  
• Click the Done button to confirm and exit. You can also select the Remove All option to remove all data stored by the listed websites.

Revise your security status

Post-factum assessment of the accuracy component in malware removal scenarios is a great habit that prevents the comeback of harmful code or replication of its unattended fractions. Make sure you are good to go by running an additional safety checkup.

Download CStealer Tojan removal tool