SkullLocker Screenlocker

Posted: June 26, 2017

Threat Metric

The Threat Meter is a malware assessment that SpywareRemove.com's research team is able to give every identifiable malware threat. Our Threat Meter includes several criteria based off of specific malware threats to value their severity, reach and volume. The Threat Meter is able to give you a numerical breakdown of each threat's initial Threat Level, Detection Count, Volume Count, Trend Path and Percentage Impact. The overall ranking of each threat in the Threat Meter is a basic breakdown of how all threats are ranked within our own extensive malware database. The scoring for each specific malware threat can be easily compared to other emerging threats to draw a contrast in its particular severity. The Threat Meter is a useful tool in the endeavor of seeking a solution to remove a threat or pursue additional analytical research for all types of computer users.

The following fields listed on the Threat Meter containing a specific value, are explained in detail below:

Threat Level: The threat level scale goes from 1 to 10 where 10 is the highest level of severity and 1 is the lowest level of severity. Each specific level is relative to the threat's consistent assessed behaviors collected from SpyHunter's risk assessment model.

Detection Count: The collective number of confirmed and suspected cases of a particular malware threat. The detection count is calculated from infected PCs retrieved from diagnostic and scan log reports generated by SpyHunter.

Volume Count: Similar to the detection count, the Volume Count is specifically based on the number of confirmed and suspected threats infecting systems on a daily basis. High volume counts usually represent a popular threat but may or may not have infected a large number of systems. High detection count threats could lay dormant and have a low volume count. Criteria for Volume Count is relative to a daily detection count.

Trend Path: The Trend Path, utilizing an up arrow, down arrow or equal symbol, represents the level of recent movement of a particular threat. Up arrows represent an increase, down arrows represent a decline and the equal symbol represent no change to a threat's recent movement.

% Impact (Last 7 Days): This demonstrates a 7-day period change in the frequency of a malware threat infecting PCs. The percentage impact correlates directly to the current Trend Path to determine a rise or decline in the percentage.

Threat Level:	8/10
Infected PCs:	55

First Seen:	June 26, 2017
OS(es) Affected:	Windows

The SkullLocker Screenlocker is a Trojan that blocks your screen indefinitely with its pop-up. While the SkullLocker Screenlocker doesn't provide an internal means of removing its window, users can recover through various methods, including built-in Windows shortcuts. Malware experts still recommend having anti-malware products uninstalling the SkullLocker Screenlocker fully while analyzing the rest of your PC for potential threats that could be installing more threatening Trojans, in addition to this one.

A Skull Having a Laugh at Your Desktop's Expense

Although they've been in circulation for years, screen-locking threats are seeing a minor Renaissance in conjunction with file-locking Trojans, which share many outer characteristics in common with them. For most threats with screen-locking payloads, their potential for making money is supported by intentional misinformation and lies. On the other hand, sometimes, malware experts find threats in this category with no greater purpose than to be a nuisance, like the SkullLocker Screenlocker.

Possibly designed as a joke, the SkullLocker Screenlocker blocks the user's screen by loading an advanced HTML window with a password input field, a background image of a skull, and some brief text telling the victim what the password is. Once they enter this code, the pop-up switches to a second message informing them that they 'cannot get out.'

Unlike most Trojans of the same type, malware experts can find no attempt at social engineering tactics like pretending to be a Windows update or legal alert. The SkullLocker Screenlocker also doesn't try to collect a ransom after locking your desktop and appears not to have any background process-based attacks running while the user can't interact with the system.

Getting Ahead of a Head Shown in Poor Taste

When analyzed independently of other threats, the SkullLocker Screenlocker is a danger only to the extent that it blocks the user interface and keeps you from using other applications. However, since the SkullLocker Screenlocker doesn't multiply itself (such as is done by worms and viruses), other threats may be implicated in its presence on your computer. These threats may install other threatening software, such as spyware or backdoor Trojans, while the SkullLocker Screenlocker keeps the desktop inaccessible to the victim.

The SkullLocker Screenlocker loads its pop-up without the standard UI elements that would let you close it, resize it, or change focus to another window. However, malware experts do ascertain that it has no built-in protection against advanced startup procedures (like Safe Mode) or keyboard shortcuts, such as the Alt+F4 command that terminates the in-focus window. No matter how you choose to suppress its symptoms, removing the SkullLocker Screenlocker during a full anti-malware scan is recommended for keeping your PC as safe as possible and reducing the chances of having any lingering components.

The SkullLocker Screenlocker may not be a money maker, but profit isn't everything to threats. Sometimes, even a bad joke has implications for your computer's safety that isn't easy to laugh out of existence.

Technical Details

File System Modifications

Tutorials: If you wish to learn how to remove malware components manually, you can read the tutorials on how to find malware, kill unwanted processes, remove malicious DLLs and delete other harmful files. Always be sure to back up your PC before making any changes.

The following files were created in the system:

file.exe

File name: file.exe
Size: 1.45 MB (1455616 bytes)
MD5: fd8245f07138ba5ee8075f018f0281d8
Detection count: 49
File type: Executable File
Mime Type: unknown/exe
Group: Malware file
Last Updated: July 6, 2017