How Hackers Find Vulnerabilities

How Do Hackers Find Vulnerabilities?

Having your personal information hacked can be a gut-wrenching experience. So how do hackers find vulnerabilities and obtain your information?

I have had the unfortunate experience of having my information compromised by a major hack. In the end, it did not affect any of my accounts. Despite this, it can be unnerving to know a breach can happen at any time.

So you may be wondering how hacking can be so successful even against prominent companies. This article will explain all about online vulnerabilities and how hackers capitalize on them. More importantly, I’ll suggest best practices so you can better protect yourself moving forward.

Hackers find vulnerabilities through many methods. These include input exploitation, session hijacking, direct object references, and cross-site scripting. Hackers find most through open-source information or trial and error.

What Vulnerability Means

A vulnerability is a weakness or soft spot that makes it possible for a computer system or software to be subject to exploits.

For example, it is not possible for programmers to anticipate with complete accuracy every possible way that every user will interact with the system.

Therefore, when skilled hackers have the motivation and take the time to analyze software, oftentimes they can manipulate weaknesses in these systems. The result is the systems respond in a way they can anticipate which is detrimental to the programmer.

The goal of the hacker can vary based on their motivations. They could be ethical hackers who do this work for fun or to alert the programmer of vulnerabilities.

Or they can be malicious hackers who attempt to disrupt business and destroy the system. Or they could have a financial motivation to steal and sell information or hold the program hostage.

Vulnerability Types in Cyber Security

It may seem worrisome from an outside perspective. But there are numerous vulnerabilities for each programming language that is public information and are current threats.

There is a fine line that developers often walk. They choose to maintain their software as open source. This means the way the software works is not secret but rather available for anyone to see.

In exchange, this great level of transparency allows ethical hackers and other developers to find and also fix vulnerabilities. As a result, making this information so easily accessible has the opposite effect of what you may originally think it would. That is to say, the code becomes stronger over time.

These vulnerabilities depend mostly on the platform or programming language as they all function differently. However, I will briefly explain some of the most common that are seen by the major languages.

Input Exploiting (SQL injections)

This encompasses more than SQL. As suggested previously in this article, it’s not possible to anticipate every combination of interactions an end-user will have with a piece of software. The core issue with this form of vulnerability is that users are able to directly input and communicate with the code.

For example, an email form may be expecting words and sentences. However, oftentimes hackers will enter special characters and codes instead. This tricks the original code. As a result, it produces a result undesired and unforeseen by the original programmer.

This vulnerability focuses on stealing information from databases stored on the website’s server. As opposed to directly from users as seen in cross-site scripting.

Fraudulent Authentication & Session Hijacking

The best way to explain this is to say this is the interception and altering of communication within the program. Hackers do this is in relation to usernames and passwords to gain overall access to accounts.

In essence, when data exchanges within a system without encryption or not properly protected, the hacker can intercept this data. They can then alter it, and then use it in order to trick this system into thinking the hacker is an authorized user.

Avoid this fatal flaw by using encryption and by not exposing session IDs in URLs.

Unnecessary Storing Sensitive Information

Computers are great for storing information especially with documents, tables, and databases. However, computer systems are not always secure for various reasons. Keeping sensitive information on-hand at all when it is not completely necessary is another vulnerability.

Simply, if the information is not present it cannot be stolen.

For example, does not collect personal information. This is because it is not necessary in order to fulfill our mission statement. Storing such data demands diligent protection that cannot always be promised.

If a hacker were to successfully infiltrate this site, there is no information that would be beneficial. Everything it contains is already public.

Insecure Direct Object References

In common words, this is a failure in programming in regards to the storage of sensitive data. When the program calls upon this information, it results in the exposure of the source of the information or its location.

Cross-site Scripting (XSS)

Cross-site scripting is a method of uploading malicious code to a website using an input field already present on the website.

You can commonly find these fields in contact forms and search bars. The malicious code inserted uses JavaScript to run actions on the computer of the visitors to the website.

Typically it redirects the user to fraudulent websites. While SQL injection steals from databases on the server, this steals data from the end-user. The theft occurs when they reach the destination site.

Now that we’ve covered the software-related vulnerabilities, I have to reveal the greatest source of all.

Social Engineering Vulnerabilities

People. “Loose lips sink ships.” Social engineering is an umbrella term that contains many types of fraud. The common link that connects all of these different methods is people. They are the source of the information leak.

The main way this happens is through deception. The details change over time but the results are the same.

Vulnerability Identification

By Mistake

The first way vulnerabilities are uncovered is by mistake. As people use a system, it’s possible for someone with a critical eye to spot a potential security flaw. They can stumble upon these issues even if they are not specifically seeking them.

When most people think about vulnerabilities it’s usually the malicious kind that comes to mind. It typically takes three factors for hackers to be successful.

The first is the technical knowledge of the platform such as the software or programming language. The next is an understanding of previous or similar vulnerabilities that worked on the platform or others. Last, it takes not only ample time but also trial and error.

Trial & Error

Hackers constantly attempt to log into my websites with administrative privileges. They appear to attempt usernames and passwords that are common for setting up web hosting accounts.

Often there are multiple attempts by the same person in a trial and error manner. They only stop when something like a black list ban prevents further attempts.

Open Sources

The other way they can be discovered is through information sharing. There are open sources, individuals with similar interests on forums, and countless guides or tutorials. Most vulnerabilities to a system are found because they have a history of happing in the past. Hackers do not have to constantly reinvent the wheel.

You’ve probably seen numerous television shows that display the phrase “based on a true story”. The writers use ideas already established with only slight changes to fit their purposes. This saves time, effort, and promotes more productivity.

Ethical Hacking

Ethical hackers see hacking as a matter of pride or duty. The ability to outsmart the original programmer is satisfying. Also, there can be a sense of duty to discover threats. This way, the developer can apply a patch to fix the security flaw and improve the security of the system.

Vulnerability Acessments

Finally, the prevention by cybersecurity experts is another way to find vulnerabilities. and others in the industry provide penetration testing in order to identify vulnerabilities before malicious hackers do.

Sometimes it feels like a race against the clock. And far too often a losing battle. There are too many people and businesses to reach. Most times we get the call after it’s too late and the data is no longer secure.

Why do vulnerabilities exist?

Codes are complex

As I mentioned above, it is impossible for a programmer to anticipate everything. There are too many combinations of inputs and ways to interact with the program.

The existence of vulnerabilities can also be due to the lack of skill or attention to detail on the part of the programmer. Human errors increase the risk that these vulnerabilities will exist.

Also, programming languages and software on which systems are built are known to have certain vulnerabilities. The owners and programmers of this software do not have control.

Lack of focus on vulnerabilities

A lack of focus on security can have disastrous results. This is described in further detail in our article in regards to the Ashley Madison hack. Sometimes, it rises to a level of negligence. But it can also be a simple case of lack of diligence.

For example, when people fail to update software, there may be an invaluable patch that fixes the vulnerability. But if the owner does not install the update, the site or system remains at risk.

Ruthlessness of hackers

None of this discounts the ruthlessness of hackers. Some of them do this full-time and as a means to support themselves financially. They may also have an amount of experience that makes them tremendously efficient and effective.

There have even been stories of hackers who, when they eventually get caught, are then hired by the government. Agencies such as the FBI hire them to work in a legitimate role.


Lastly, many countries employ professional hackers in order to gain an advantage on the global stage. As a result of being funded directly by a country and the ample resources at their disposal, they can be exceptionally effective.

There is also the promise of great reward for obtaining data. It can then be used either directly to effect financial fraud or can be used as a form of ransom. Sometimes hackers are caught and charged with federal crimes by the US Justice Department.

Importance of Vulnerability Assessments

A strong offense is a strong defense. Unless you are in law enforcement, it’s not legal or practical to track down hackers as a preventative measure to protect your systems.

Instead, understand and accept that your project will inevitably be attacked. Since you can anticipate an attack, it proves useful to anticipate the tactics. Depending on which tactics will be used and which loopholes may be found, apply safeguards as possible.

By finding avenues of attack, cybersecurity experts can close the gaps. Once the hackers are successful it’s too late.

What’s at stake

The following are examples of famous costly hacks. The data breach that affected Experian had the potential to financially ruin the millions of victims who had their sensitive information compromised.

More information about the data breaches affecting the three major credit reporting agencies is available in our article annual-credit-report.

Account breaches also have the potential to embarrass people such as the iCloud leak affecting many celebrities. Their private photos were publicly released to the public. Many of these pictures were extremely exposing and certainly caused a big emotional impact for the victims.

It’s also possible these data breaches ruin relationships simply by identifying users of the service. This was seen in the Ashley Madison hack where cheating spouses were exposed. Our article answering if Ashley Madison is a safe site goes into more detail.

How to Not Get Hacked

There is no 100% foolproof way to prevent hackers. If there were everyone would implement these measures. And hackers would cease to exist. The best you can hope for is to build a sufficient number of security layers.

Hopefully, hackers hit enough roadblocks they go looking for softer targets. The lowest hanging fruit gets picked the quickest. Hackers are people too and they won’t work harder than necessary.

One layer of security that time and time again proofs to be effective is to install software updates. This way security patches that are discovered over time can be applied.

A less obvious method is mindfulness. Consider the information you are revealing about yourself.

Surveys both online and in-person are information collecting tools. They bill themselves as having a specific goal. It is suggested your information will only be used for that purpose. But it is unlikely you will ever know how your information is being stored and you cannot guarantee its safety.

It comes down to mindset

Often programmers focus on performance and not security. Being security-minded as you code will make it easier to go back later and sure up any leaks.

Taking time is also important. This means reserving a portion of your schedule at the end of a project to focus only on security. This is something you don’t want to be doing for the first time when the project is live.

If you’re a programmer, check out our article about the Best JavaScript Obfuscator, which can make your code more secure.


Your personal information is not safe online. There are more vulnerabilities than you may be aware of. With the motivation of high monetary reward, hackers use open-source information, hacking forums, and hours of trial and error to find success.

All too often there are major breaches. Afterward, you’re given the option of free credit monitoring. It’s a good idea to take this option. Especially if you do not already subscribe to a monitoring service.

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