Blue Screen Of Death (BSOD)

 A Blue Screen Of Death, or officially known as the STOP Error is a system crash happening due to hardware or driver(software) errors. A STOP Error can also be caused by a critical boot loader error, where the operating system is unable to start from the bootable drive due to the presence of an incorrect disk driver, a damaged file system, or a similar problem.

The Blue Screen of Death

While it may seem odd to think about purposefully causing a Blue Screen Of Death (BSOD), Microsoft includes such a provision in Windows XP (Vista also). This might come in handy for testing and troubleshooting your Startup And Recovery settings, Event logging, and for demonstration purposes.

Here's how to create a BSOD:

Launch the Registry Editor (Regedit.exe).
Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\i8042prt\Parameters.
Go to Edit, select New | DWORD Value and name the new value CrashOnCtrlScroll.
Double-click the CrashOnCtrlScroll DWORD Value, type 1 in the Value Data textbox, and click OK.
Close the Registry Editor and restart Windows XP.
When you want to cause a BSOD, press and hold down the [Ctrl] key on the right side of your keyboard, and then tap the [ScrollLock] key twice. Now you should see the BSOD.

If your system reboots instead of displaying the BSOD, you'll have to disable the Automatically
Restart setting in the System Properties dialog box. To do so, follow these steps:

Press [Windows]-Break.
Select the Advanced tab.
Click the Settings button in the Startup And Recovery panel.
Clear the Automatically Restart check box in the System Failure panel.
Click OK twice.

Here's how you remove the BSOD configuration:

Launch the Registry Editor (Regedit.exe).
Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\i8042prt\Parameters.
Select the CrashOnCtrlScroll value, pull down the Edit menu, and select the Delete command.
Close the Registry Editor and restart Windows XP.
Note: Editing the registry is risky, so make sure you have a verified backup before making any changes.

Additional Note on the steps provided to create a BSOD :
Hackers can make use of this trick to crash your computer over and over again by simply creating a .vbs or .bat file which will change the values in the Registry, and then pressing the keys needed automatically.

References:
-http://en.wikipedia.org/wiki/Blue_Screen_of_Death
-http://psacake.com/web/jr.asp

Fixing the BSOD : http://support.microsoft.com/kb/958233


Thank you for reading.
Cyber Frost

Types of Computer Viruses

Bootsector Virus:

A virus which attaches itself to the first part of the hard disk that is read by the computer upon bootup. These are normally spread by floppy disks.

Note: Floppy disks are kind of outdated, so, perhaps, it's spread through portable hard disks or boot CDs.

Macro Virus:

Macro viruses are viruses that use another application's macro programming language to distribute themselves. They infect documents such as MS Word or MS Excel and are typically spread to other similar documents.

This is a nightmare to every office workers. Once your computer is infected, your whole documents will be destroyed. So, always do backups!
 
Memory Resident Viruses:
Memory Resident Viruses reside in a computers volitale memory (RAM). They are initiated from a virus which runs on the computer and they stay in memory after it's initiating program closes.

Rootkit Virus:
A rootkit virus is an undetectable virus which attempts to allow someone to gain control of a computer system. The term rootkit comes from the linux administrator root user. These viruses are usually installed by trojans and are normally disguised as operating system files.

Polymorphic Viruses:
Well, poly means many and morph means form. So, this type of virus will replicate itself into many forms of file. Now, you might see it as a .pdf file. Next time you log in, it might have changed itself into a .dll file. It is extremely difficult to detect manually. Even some antivirus might miss it while scanning for viruses.

Logic Bombs/Time Bombs:
These are viruses which are programmed to initiate at a specific date or when a specific event occurs. Some examples are a virus which deletes your photos on Halloween, or a virus which deletes a database table if a certain employee gets fired.

This is my favorite type of virus, it is completely unpredictable, only the coder of the virus knows what will happen and when it will happen.
DeepFreeze might be able to counter this type of virus.

Important Note:
Knowing that viruses have a very big effect on your computer, you might want to update your firewalls and antivirus for protection. Everyday, hundreds(maybe thousands) of new viruses are made, with even more creative ways of infecting and surviving.

So, always keep your antivirus and firewalls up-to-date. However, do not get trapped by those fake antivirus providers. Only use trusted antivirus brands, such as Avira, Norton, AVG(Grisoft), and NOD32.


Thanks for reading.
Cyber Frost

The Difference Between a Virus, a Worm, and a Trojan Horse

Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three.

One common mistake that people make when the topic of a computer virus arises is to refer to a worm or Trojan horse as a virus. While the words Trojan, worm and virus are often used interchangeably, they are not exactly the same thing. Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three, and knowing those differences can help you better protect your computer from their often damaging effects.

What Is a Virus?

A computer virus attaches itself to a program or file enabling it to spread from one computer to another, leaving infections as it travels. Like a human virus, a computer virus can range in severity: some may cause only mildly annoying effects while others can damage your hardware, software or files. Almost all viruses are attached to an executable file, which means the virus may exist on your computer but it actually cannot infect your computer unless you run or open the malicious program. It is important to note that a virus cannot be spread without a human action, (such as running an infected program) to keep it going. Because a virus is spread by human action people will unknowingly continue the spread of a computer virus by sharing infecting files or sending emails with viruses as attachments in the email.

What Is a Worm?

A worm is similar to a virus by design and is considered to be a sub-class of a virus. Worms spread from computer to computer, but unlike a virus, it has the capability to travel without any human action. A worm takes advantage of file or information transport features on your system, which is what allows it to travel unaided.
The biggest danger with a worm is its capability to replicate itself on your system, so rather than your computer sending out a single worm, it could send out hundreds or thousands of copies of itself, creating a huge devastating effect. One example would be for a worm to send a copy of itself to everyone listed in your e-mail address book. Then, the worm replicates and sends itself out to everyone listed in each of the receiver's address book, and the manifest continues on down the line.
Due to the copying nature of a worm and its capability to travel across networks the end result in most cases is that the worm consumes too much system memory (or network bandwidth), causing Web servers, network servers and individual computers to stop responding. In recent worm attacks such as the much-talked-about Blaster Worm, the worm has been designed to tunnel into your system and allow malicious users to control your computer remotely.

What Is a Trojan horse?

A Trojan Horse is full of as much trickery as the mythological Trojan Horse it was named after. The Trojan Horse, at first glance will appear to be useful software but will actually do damage once installed or run on your computer.  Those on the receiving end of a Trojan Horse are usually tricked into opening them because they appear to be receiving legitimate software or files from a legitimate source.  When a Trojan is activated on your computer, the results can vary. Some Trojans are designed to be more annoying than malicious (like changing your desktop, adding silly active desktop icons) or they can cause serious damage by deleting files and destroying information on your system. Trojans are also known to create a backdoor on your computer that gives malicious users access to your system, possibly allowing confidential or personal information to be compromised. Unlike viruses and worms, Trojans do not reproduce by infecting other files nor do they self-replicate.



Source: http://www.webopedia.com/