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17 entries found.
Updated on Dec 16, 2009

Windows Defender detects and removes this threat.

This threat stops you from loading Windows and displays a full-screen message, commonly called a "lock screen". If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

It tries to scare you into paying a fine or texting a premium-charge phone number to unlock your PC.

You can read more on our ransomware page.

Alert level: severe
Updated on Jan 19, 2010
Trojan:Win32/LockScreen.gen!A is a detection for a trojan that displays a graphic image with adult content and prevents closing or dismissing the image.
Alert level: severe
Updated on Jul 02, 2010

Microsoft Defender Antivirus detects and removes this threat.

This threat stops you from loading Windows and displays a full-screen message, commonly called a "lock screen". If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

It tries to scare you into paying a fine to unlock your PC.

Our ransomware FAQ page has more information on this type of threat.

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.

Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.

Alert level: severe
Updated on Aug 09, 2010
Trojan:Win32/Calelk.H is a trojan that seizes control of the infected computer by locking the screen and preventing the user from using the computer, while displaying pornographic images in an attempt to persuade the user to send an SMS to a specific number.
Alert level: severe
Updated on Sep 24, 2010

Microsoft Defender Antivirus detects and removes this threat.

This threat stops you from loading Windows and displays a full-screen message, commonly called a "lock screen". If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

It tries to scare you into paying a fine or texting a premium-charge phone number to unlock your PC.

You can read more on our ransomware page.

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.

Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.

Alert level: severe
Updated on Dec 19, 2010
Trojan:Win32/Calelk.C is a trojan that prevents the affected user from using their computer, and displays a pornographic image. The affected user is then instructed to send an SMS to a specified number in order to unlock their computer.
Alert level: severe
Updated on Jan 27, 2011
Microsoft Defender Antivirus detects and removes this threat. 

The threat locks your screen and prevents you from using your desktop. It shows you a message saying that if you want to regain access to your desktop, you have to pay a fine in the form of an SMS sent to a premium number.

This type of threat is known as ransomware.

Our ransomware FAQ page has more information on this type of threat.

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.

Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.

Alert level: severe
Updated on Feb 04, 2011
Trojan:Win32/Calelk.A is a trojan that gains control of the infected computer by locking the screen and preventing the user from using the computer. It then prompts the user to send an SMS to a premium number. Some variants may display adult images.
Alert level: severe
Updated on Feb 04, 2011
TrojanDropper:Win32/Mianoot.A is the detection for a trojan that drops and runs other malicious components into the affected computer.
Alert level: severe
Updated on May 21, 2012
Windows Defender Antivirus detects and removes this threat. 
 
This family of ransomware trojans targets people from certain countries. It locks your PC and displays a localized webpage that covers your desktop. This webpage demands the payment of a fine for the supposed possession of illicit material.

Some variants might also take webcam screenshots, play an audio message pretending to be from the FBI, closes or stops processes or programs, and prevents certain drivers from loading in safe mode - possibly to stop you from attempting to disable the trojan.

Variants of Trojan:Win32/Tobfy might make lasting changes to your PC that make it difficult for you to download, install, run, or update your antivirus software.

Alert level: severe
Updated on Jun 10, 2011

Microsoft Defender Antivirus detects and removes this threat.

This threat stops you from loading Windows and displays a full-screen message, commonly called a "lock screen". If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

It tries to scare you into paying a fine or texting a premium-charge phone number to unlock your PC.

You can read more on our ransomware page.

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.

Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.

Alert level: severe
Updated on Oct 27, 2011

Microsoft Defender Antivirus detects and removes this threat.

This threat stops you from loading Windows and displays a full-screen message, commonly called a "lock screen". If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

It tries to scare you into paying a fine to unlock your PC.

You can read more on our ransomware page.

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.

Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.

Alert level: severe
Updated on Jul 13, 2012

Trojan:Win32/Tobfy.A is a ransomware that prevents you from accessing your desktop by covering the desktop with a certain image.

Alert level: severe
Updated on Sep 12, 2012

This ransomware prevents you from accessing your computer. It covers your entire desktop with an image pretending to be from your local authorities, asking you to pay a fine to regain access. The image covering the desktop is downloaded from a certain website.

Alert level: severe
Updated on Nov 06, 2012

Trojan:Win32/Tobfy.I a ransomware trojan that targets users from certain countries. It locks your computer and displays a localized webpage that covers your desktop. It demands the payment of a fine for the supposed possession of illicit material.

Alert level: severe
Updated on Jan 30, 2014

Windows Defender detects and removes this threat.

It lets a malicious hacker access and control your PC from a command and control server (C&C).

It also lowers the security settings for Internet Explorer.

You can read more about this threat on the Microsoft Malware Protection Center (MMPC) blog: 

Find out ways that malware can get on your PC.  

Alert level: severe
Updated on Sep 08, 2014
Alert level: severe