LET’S TALK ABOUT HACKERS - PART 2

LET’S TALK ABOUT HACKERS - PART 2

Main Concept: A cracker or cracking is to "gain unauthorized access to a computer in order to commit another crime such as destroying information contained in that system"

HACKING TECHNIQUES AND OTHERS:

VULNERABILITY SCANNER: A vulnerability scanner is a tool used to quickly check computers on a network for known weaknesses. Hackers also commonly use port scanners. These check to see which ports on a specified computer are "open" or available to access the computer, and sometimes will detect what program or service is listening on that port, and its version number.

FINDING VULNERABILITIES: Hackers may also attempt to find vulnerabilities manually. A common approach is to search for possible vulnerabilities in the code of the computer system then test them, sometimes reverse engineering the software if the code is not provided.

BRUTE-FORCE ATTACK: Password guessing. This method is very fast when used to check all short passwords, but for longer passwords other methods such as the dictionary attack are used, because of the time a brute-force search takes.

PASSWORD CRACKING: Password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system. Common approaches include repeatedly trying guesses for the password, trying the most common passwords by hand, and repeatedly trying passwords from a "dictionary", or a text file with many passwords.

PACKET ANALYZER: A packet analyser ("packet sniffer") is an application that captures data packets, which can be used to capture passwords and other data in transit over the network.

SPOOFING ATTACK (PHISHING): A spoofing attack involves one program, system or website that successfully masquerades as another by falsifying data and is thereby treated as a trusted system by a user or another program — usually to fool programs, systems or users into revealing confidential information, such as user names and passwords.

ROOTKIT: A rootkit is a program that uses low-level, hard-to-detect methods to subvert control of an operating system from its legitimate operators. Rootkits usually obscure their installation and attempt to prevent their removal through a subversion of standard system security. They may include replacements for system binaries, making it virtually impossible for them to be detected by checking process tables.

SOCIAL ENGINEERING: In the second stage of the targeting process, hackers often use Social engineering tactics to get enough information to access the network. They may contact the system administrator and pose as a user who cannot get access to his or her system. 

THIS ONE IS NOT RELATED WITH SOCIAL NETWORKS!

Hackers who use this technique must have cool personalities, and be familiar with their target's security practices, in order to trick the system administrator into giving them information. In some cases, a help-desk employee with limited security experience will answer the phone and be relatively easy to trick. Another approach is for the hacker to pose as an angry supervisor, and when his/her authority is questioned, threaten to fire the help-desk worker. Social engineering is very effective, because users are the most vulnerable part of an organization. No security devices or programs can keep an organization safe if an employee reveals a password to an unauthorized person.

Social engineering can be broken down into four sub-groups:

-      Intimidation As in the "angry supervisor" technique above, the hacker convinces the person who answers the phone that their job is in danger unless they help them. At this point, many people accept that the hacker is a supervisor and give them the information they seek.

-      Helpfulness The opposite of intimidation, helpfulness exploits many people's natural instinct to help others solve problems. Rather than acting angry, the hacker acts distressed and concerned. The help desk is the most vulnerable to this type of social engineering, as (a.) its general purpose is to help people; and (b.) it usually has the authority to change or reset passwords, which is exactly what the hacker wants.

-      Name-dropping The hacker uses names of authorized users to convince the person who answers the phone that the hacker is a legitimate user him or herself. Some of these names, such as those of webpage owners or company officers, can easily be obtained online. Hackers have also been known to obtain names by examining discarded documents (so-called "dumpster diving").

-      Technical Using technology is also a way to get information. A hacker can send a fax or email to a legitimate user, seeking a response that contains vital information. The hacker may claim that he or she is involved in law enforcement and needs certain data for an investigation, or for record-keeping purposes.

TROJAN HORSES: A Trojan horse is a program that seems to be doing one thing but is actually doing another. It can be used to set up a back door in a computer system, enabling the intruder to gain access later. (The name refers to the horse from the Trojan War, with the conceptually similar function of deceiving defenders into bringing an intruder into a protected area.)

COMPUTER VIRUS: A virus is a self-replicating program that spreads by inserting copies of itself into other executable code or documents. By doing this, it behaves similarly to a biological virus, which spreads by inserting itself into living cells. While some viruses are harmless or mere hoaxes, most are considered malicious.

COMPUTER WORM: Like a virus, a worm is also a self-replicating program. It differs from a virus in that (a.) it propagates through computer networks without user intervention; and (b.) does not need to attach itself to an existing program. Nonetheless, many people use the terms "virus" and "worm" interchangeably to describe any self-propagating program.

KEYSTROKE LOGGING: A keylogger is a tool designed to record ("log") every keystroke on an affected machine for later retrieval, usually to allow the user of this tool to gain access to confidential information typed on the affected machine. Some keyloggers use virus-, trojan-, and rootkit-like methods to conceal themselves. However, some of them are used for legitimate purposes, even to enhance computer security. For example, a business may maintain a keylogger on a computer used at a point of sale to detect evidence of employee fraud.

TOOLS AND PROCEDURES: A thorough examination of hacker tools and procedures may be found in Cengage Learning's E|CSA certification workbook.

HACKER CLASSIFICATION

Several subgroups of the computer underground with different attitudes use different terms to demarcate themselves from each other, or try to exclude some specific group with whom they do not agree. Members of the computer underground should be called crackers.

1. WHITE HAT: A white hat hacker breaks security for non-malicious reasons, either to test their own security system, perform penetration tests or vulnerability assessments for a client - or while working for a security company which makes security software.
2. BLACK HAT: A "black hat" hacker is a hacker who "violates computer security for little reason beyond maliciousness or for personal gain". Black hat hackers form the stereotypical, illegal hacking groups often portrayed in popular culture, and are "the epitome of all that the public fears in a computer criminal".
3. GREY HAT: A grey hat hacker lies between a black hat and a white hat hacker. A grey hat hacker may surf the Internet and hack into a computer system for the sole purpose of notifying the administrator that their system has a security defect.
4. ELITE HACKER: A social status among hackers, elite is used to describe the most skilled. Newly discovered exploits circulate among these hackers. Elite groups such as Masters of Deception conferred a kind of credibility on their members.
5. SCRIPT KIDDIE: A script kiddie (known as a skid or skiddie) is an unskilled hacker who breaks into computer systems by using automated tools written by others, usually with little understanding of the underlying concept.
6. NEOPHYTE: A neophyte ("newbie", or "noob") is someone who is new to hacking or phreaking and has almost no knowledge or experience of the workings of technology and hacking.
7. BLUE HAT: A blue hat hacker is someone outside computer security consulting firms who is used to bug-test a system prior to its launch, looking for exploits so they can be closed.
8. HACKTIVIST: A hacktivist is a hacker who utilizes technology to publicize a social, ideological, religious or political message. Can be divided into two main groups: Cyberterrorism: Activities involving website defacement or denial-of-service attacks. Freedom of information: Making information that is not public, or is public in non-machine-readable formats, accessible to the public.
9. NATION STATE: Intelligence agencies and cyberwarfare operatives of nation states. 
10. ORGANIZED CRIMINAL GANGS: Groups of hackers that carry out organized criminal activities for profit.

 

RANSOMEWARE, WHAT IS AND HOW DOES IT WORKS

RANSOMEWARE, WHAT IS AND HOW DOES IT WORKS?

Ransomware is computer malware that installs covertly on a victim's computer, executes a cryptovirology attack that adversely affects it, and demands a ransom payment to decrypt it or not publish it.

Simple ransomware may lock the system in a way which is not difficult for a knowledgeable person to reverse, and display a message requesting payment to unlock it. More advanced malware encrypts the victim's files, making them inaccessible, and demands a ransom payment to decrypt them.

The ransomware may also encrypt the computer's Master File Table (MFT) or the entire hard drive. Thus, ransomware is a denial-of-access attack that prevents computer users from accessing files since it is intractable to decrypt the files without the decryption key. 

MECHANISM:

ATTACKER -> VICTIM: The attacker generates a key pair and places the corresponding public key in the malware. The malware is released.

VICTIM -> ATTACKER: To carry out the cryptoviral extortion attack, the malware generates a random symmetric key and encrypts the victim's data with it. It uses the public key in the malware to encrypt the symmetric key. The victim sends the asymmetric ciphertext and e-money to the attacker.

ATTACKER -> VICTIM: The attacker receives the payment, deciphers the asymmetric ciphertext with his private key, and sends the symmetric key to the victim. The victim deciphers the encrypted data with the needed symmetric key thereby completing the cryptovirology attack.

CRYPTOLOCKER

Encrypting ransomware reappeared in September 2013 with a Trojan known as CryptoLocker, which generated a 2048-bit RSA key pair and uploaded in turn to a command-and-control server, and used to encrypt files using a whitelist of specific file extensions. The malware threatened to delete the private key if a payment of Bitcoin or a pre-paid cash voucher was not made within 3 days of the infection. Due to the extremely large key size it uses, analysts and those affected by the Trojan considered CryptoLocker extremely difficult to repair. Even after the deadline passed, the private key could still be obtained using an online tool, but the price would increase to 10 BTC—which cost approximately US$2300 as of November 2013.

CRYPTOLOCKER.F

The Trojans spread via fraudulent e-mails claiming to be failed parcel delivery notices from the Post Service; to evade detection by automatic e-mail scanners that follow all links on a page to scan for malware, this variant was designed to require users to visit a web page and enter a CAPTCHA code before the payload is actually downloaded, preventing such automated processes from being able to scan the payload.

TORRENTLOCKER

Contained a design flaw comparable to CryptoDefense; it used the same keystream for every infected computer, making the encryption trivial to overcome. However, this flaw was later fixed. In November 2014, it was estimated that over 9,000 users had been infected by TorrentLocker in Australia and Turkey with 11,700 infections.

CRYPTOWALL

Appeared in 2014 and was distributed as part of a malvertising campaign on the Zedo ad network in September 2014 that targeted several major websites; the ads redirected to rogue websites that used browser plugin exploits to download the payload. CryptoWall 3.0 used a payload written in JavaScript as part of an email attachment, which downloads executables disguised as JPG images. The malware creates new instances of explorer.exe and svchost.exe to communicate with its servers. When encrypting files, the malware also deletes volume shadow copies, and installs spyware that steals passwords and Bitcoin wallets.

The FBI reported in June 2015 that nearly 1,000 victims had contacted the bureau's Internet Crime Complaint Center to report CryptoWall infections, and estimated losses of at least $18 million.

The most recent version, CryptoWall 4.0, enhanced its code to avoid antivirus detection, and encrypts not only the data in files but also the file names.

WHY RANSOMWARE ATTACKS HOME USERS:

• Don’t have data backups
• They don’t keep their software up to date (even if specialists always nag them to);
• They fail to invest in need-to-have cyber security solutions;
• They often rely on luck to keep them safe online (i can’t tell you how many times i’ve heard “it can’t happen to me”);
• Most home users still rely exclusively on antivirus to protect them from all threats, which is frequently ineffective in spotting and stopping ransomware;
• The same lack of online safety awareness makes them prone to manipulation by cyber attackers;
• Of the sheer volume of internet users that can become potential victims (more infected pcs = more money).
• They have little or no cyber security education, which means they’ll click on almost anything

 

WHY RANSOMWARE ATTACKS TARGET BUSINESSES:

• That’s where the money is;
• Small businesses are often unprepared to deal with advanced cyber attacks (which ransomware is) and have a lax byod (bring your own device) policy.
• Cyber criminals know that business would rather not report ransomware attacks for fears of legal or reputation-related consequences;
• The human factor is still a huge liability which can also be exploited, but through social engineering tactics;
• Computer systems in companies are often complex and prone to vulnerabilities that can be exploited through technical means;
• Ransomware can affect not only computers, but also servers and cloud-based file-sharing systems, going deep into a business’s core;
• Attackers know that ransomware can cause major business disruptions, which will increase their chances of getting paid;

COMMON METHODS SPREAD RANSOMWARE:

• Spam email campaigns that contain malicious links or attachments
• Legitimate websites that have malicious code injected in their web pages;
• Internet traffic redirects to malicious websites;
• Drive-by downloads;
• Malvertising campaigns;
• Security exploits in vulnerable software;
• SMS messages (mobile devices);
• Botnets;
• Affiliate schemes in ransomware-as-a-service
• Self-propagation (spreading from one infected computer to another);

HOW TO BE SAFE AND CLEAN:

1. Understand the importance of having a traffic-filtering solution that can provide
2. Proactive anti-ransomware protection.
3. Don’t store all important data on the pc, look for another options: external drives and cloud
4. 2 backups data: external hard drive and cloud
5. Removed automatic updates or set the browser to ask me if i want to activate these plugins when needed (adobe flash, adobe reader, java and Silverlight
6. Manually sync the data to keep away all “open doors” of infections: manually to a hard drive and the cloud. This process can be hard but safe
7. Operating system and software up to date, including the latest security updates
8. Don’t use an administrator account on daily basis. Use a guest account with limited privileges.
9. Removed outdated plugins and add-ons from browsers
10. Turn off macros in word, excel, PowerPoint, etc.
11. Never open spam emails or emails from unknown senders
12. Never download attachments from spam emails or suspicious emails
13. Never click links in spam emails or suspicious emails
14. Use a reliable, paid antivirus product that includes an automatic update module and a real-time scanner
15. Adjusted my browsers security and privacy settings for increased protection.
16. Add a “ad blocker” to avoid the threat of malicious ads

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REASONS TO REPLACE YOUR COMPUTER FAN AND HEATSINK

REASONS TO REPLACE YOUR COMPUTER FAN AND HEATSINK

A computer's fan and heatsink are two of its most important components. The primary role of both is to cool down the processor and keep it from overheating. A laptop or notebook does not have to be outside in hot, humid weather to overheat. In fact, even if a computer is kept away from extreme heat altogether, it can still overheat. That is because a computer's processor is responsible for processing information and giving instructions to other components in the computer. A processor can get very busy as a result, especially when it is running multiple programs simultaneously. As a result, it heats up, and if there is nothing to cool it down, it can malfunction and break down, costing the owner hundreds or even thousands of dollars. This is why a good fan and heatsink are necessary.

The more demand placed on the processor, the more effective the fan and heatsink must be. This guide identifies five issues that can cause or indicate improper or insufficient functioning of the fan and heatsink to help users better understand why and when they should replace their fans and heatsinks. This guide also discusses how to find a compatible make and model for your desktop or laptop.

HOW A FAN AND HEATSINK WORK

Explaining how a fan and heatsink work with processors helps readers to understand why they may run into problems. Cooling a computer is a process in itself, and understanding how that works gives better insight as to what kind of problems may occur during it. Certain problems are indicative of the need for new components. The two need to be working together for optimal performance.

 

The heatsink portion of the unit acts as a thermal conductor. This means it draws in the heat the processor gives off. The principle behind this thermal conduction is the slower molecules of the heatsink's metal draw in the energy given off by the fast moving molecules of the warm processor. This creates an equilibrium, heating the heatsink and cooling the processor.

Heatsinks employ either aluminium or copper. Aluminium, though capable of conducting a good amount of heat, has a lower thermal conduction rating than copper. However, copper is heavier than aluminium, which puts a strain on the motherboard since it holds the heatsink. If a user has a big, sturdy motherboard that can hold a copper heatsink, then copper is preferable for its stronger thermal conduction properties. A heatsink usually comes in a 120 or 140-mm size.

The heatsink's job is to absorb warmth from the processor, but that warmth still needs a place to go. That is where the fan comes into play. The cooling fan comes in 3-pin or 4-pin and is typically around 25mm in size, but it packs a punch. The fan moves air across the heatsink and out of the computer, cooling both the heatsink and the computer. Many heatsinks have an additional fan—this is sometimes called a dual fan—that sits above the heatsink and blows air onto the processor to cool that down as well. Heatsinks without an extra fan are called passive heatsinks, and those with an extra fan are called active heatsinks. Because the components come in different sizes, it is important to check the size and shape of the connector with the corresponding size and shape of the one on the motherboard. You can find it out online as well.

There are also liquid cooling or "water cooler" options available for cooling down computers, but these are high-end systems that come with a high price tag. The main benefit of CPU coolers is that they are quiet—even silent. However, they are far more complex than the traditional fan and heatsink cooling system.

ISSUES WARRANTING REPLACEMENT OF A FAN AND HEATSINK

A few common instances might lead a user to need to replace the fan and heatsink on their computer. Some of these issues might have to do directly with them, while others are indirect issues that affect the processor.

1- DAMAGED OR BROKEN FAN

Just like any other moving part, a fan can break down over time. After enough use, even the best ones are bound to stop working. If it becomes damaged or broken, it must be replaced. Fortunately, it can be purchased as a separate part, allowing for continued use of the heatsink. It is advisable to check for compatibility first though.

Many systems have their Basic Input Output System (BIOS) set to recognize certain fan speeds and therefore may not recognize a fan that does not blow at the same speed as the original fan. This can cause the computer to not power up. As a result, it is best to check with the manufacturer as to which fans are compatible with the system in question.

2- EXCESSIVE NOISE

The fan is likely not be completely silent, but it should be quiet, and it should never be loud. Excessive noise is actually not a problem in and of itself. Rather, it is a symptom of a failing fan. If a user is hearing excessive noise coming from their machine, it is possible the fan has come loose, which is a problem that can be rectified. However, it may also mean that the fan is not rotating properly. If this is the case, it probably is not doing a sufficient job of cooling the system and may therefore be in need of replacement before the entire system overheats and fails. Replacing an entire system would be a great deal more expensive than just replacing its fan.

3- MELTING DUE TO OVERUSE

Just as a fan can break down from overuse, so can a heatsink. Because a heatsink absorbs the heat from a processor, it can become hot as well, especially if there is no fan to cool it and if the processor gives off a great deal of heat. A heatsink can actually melt if it becomes too hot, and if this happens, the heatsink will not work properly. When it begins to melt, it is time to get a new one. Running a system with a faulty heatsink can quickly destroy the processor and melt the motherboard, rendering the system useless. As with the fan, replacing the heatsink is a much less expensive fix than replacing an entire system.

4- UPGRADES IN THE SYSTEM

Direct problems with the fan or heatsink are not the only cases that require a new fan and heatsink. Upgrades to the system, such as adding a new graphics card or replacing the processing unit, RAM, and motherboard could all necessitate a new fan and heatsink. Not all fans and heatsinks are able to cool the heat that more powerful versions of these pieces of hardware produce. Each device generally indicates how much heat it creates, thereby allowing users to determine whether their fans and heatsinks are capable of cooling them.

5- RUNNING POWERFUL SOFTWARE

Running powerful software is another indirect issue that may necessitate a new fan and heatsink. The processor may begin to run hot if the software puts a strain on it. Ideally, a user will install a new processor if the current one struggles to run the software, but a new fan and heatsink can provide a temporary fix. It keeps the processor cool, which will prevent the motherboard from being irreparably damaged. Replacing the latter would be a much more expensive fix, and it is best to avoid this if at all possible.

In other words…

Where to Buy a Fan and Heatsink

One good place to look is a shop that sells computer goods. Some carry relatively a large stock of fans and heatsinks, but it is not usually as extensive as those found in online stores. In the latter, the inventory can be vast and thereby offer consumers the largest selection.

Those looking for used fans and heatsinks have a couple of options. Computer repair shops often salvage parts from machines that no longer work. If the problem is not related to the fan or heatsink, the shop generally resells these parts after they have been removed. It is also possible to find fans and heatsinks on online classifieds.

How to Buy a Fan and Heatsink on eBay

eBay is a good online source for fans and heatsinks because they have a large stock of this kind of computer hardware, and the site gives you the tools that you need to make sure  you are buying from a reputable seller.

Searching eBay for Fans and Heatsinks

It's easy to find the fan or heatsink you need on eBay. Simply use the Search bar located at the top of any page and enter keywords related to what you're looking for. For instance, "computer fans", "heatsinks", or "fans with heatsinks", depending on your needs. You can also filter your search further by selecting certain features for the fan, heatsink, or fan and heatsink combination. For example, if you need a new heatsink for a Dell computer, you can select Dell under the Brand menu after you pull results for all heatsinks. If you want to save a bit of money by buying a used heatsink, you can select Used from the Condition menu and all of the used Dell heatsinks for sale are listed.

Finding Reputable Sellers

eBay has two ways to help you find reputable sellers. The first is by letting you see sellers' feedback. This is where buyers leave their impressions from their buying experiences with sellers. If a seller has good feedback from many customers, you are likely to have a good buying experience with that seller. The second way that eBay helps you to find reputable sellers is by identifying the sellers with the best feedback.

CONCLUSION

A computer's fan and heatsink are necessary components to keep a computer's processor cool. This is important because the processor is perhaps the most important piece of hardware on a computer (and the more expensive! after the information based on the PC). 

Once it stops working, the whole system stops working. Even worse, a computer that runs hot risks melting the motherboard, which can cause even more extensive damage and necessitate the replacement of the entire desktop or laptop. Although the fan and heatsink may not be the most technologically advanced components in a computer, they are some of the most important due to their preventive role in a consequential chain that could lead to the breakdown of an entire system. 

It is important that users learn the cooling capacities of their fans and heatsinks and how to detect direct problems with these devices. Doing so can help to prevent worse, and more expensive, damage being done to the system.

ANOTHER CONSIDERATIONS:

• Run a schedule and maintenance plan for your computer (can be at 3/6/12 months)
• If you can't or have the knowledge skills to do it, pay a tech support for maintenance and it will cost from $35-$75
• Always consider your place at work or home and where is located the PC. For example: the PC can be closer in a window and dust, sun and other components can damage the PC and the maintenance has to be done more often
• Nobody better than you, knows how much time does the computer is turned on and working overload
• Plan to buy all components together, at least can reclaim warranty and estimate when and how is a upgrade need it
• I cannot tell you what brand, model or specifications of CPU Cooler you can buy. This is according of the computer type you own (brand, model and use of the system) and you can google it and research CPU Coolers with heatsink.

Tell me what do you think about this article, did you like it? does the information was useful? let me know your thoughts!