SQL injection can be best defined as a security vulnerability on your web application. With this injection, an attacker can tamper with or misappropriate the queries that your application would be sent to your database. What’s more, with an SQL injection, cybercriminals can access data that they otherwise cannot access. The data includes everything ranging from customer information, third-party user information, or any other data that the application stores. In case the attacker successfully deletes or tampers with this data, the application would be rendered inaccessible. In the majority of the cases, this is the situation and over time it affects the behavior of the application.
Depending on the situation, attackers can also escalate these injections to modify server details or your back-end environment. Depending on the severity of the situation, you may even be subject to denial-of-service attacks.
In this article, we will learn all about SQL injection along with SQL injection examples. This way, you will have a clear picture of the severity of the attack and the way it is typically performed.
What happens after an SQL attack?
One of the biggest questions for many is probably the impact of an SQL attack. In this bit, we will discuss all that and more in detail. Most SQL attacks end up with unauthenticated and unauthorized contact and access with third-party user data and other sensitive details. This can be anything starting from password, to debit and/or credit card information, along with any other information that the user might have provided. Over the last couple of years, some of the biggest data breaches have happened due to these SQL injections which ultimately affect the reputation of your organization and increase the amount of regulatory or federal fines you might have to pay. Depending on the situation, attackers can access your organization’s backdoor, which might result in a major, often overlooked compromise, for the longest time.
Typically, the following events are likely to happen during and after an SQL injection attack.
- The attackers will potentially tamper with your identity along with existing details to cause multiple issues such as preventing transactions, modifying the existing balances, or completely displaying third-party user data in your system. Depending on the severity of the situation, it can affect your data to make it completely inaccessible and unavailable. The individuals performing the attack will assume the admin ownership of your system.
- If you don’t already know, the most susceptible to SQL injections are PHP and ASP applications. This is primarily because their typical interface is outdated and old. Because most .Net and J2EE applications come with in-built program interfaces, they won’t be attacked by SQL injections per se.
- The impact of the SQL injection entirely depends on the skill and the imagination of the attacker. Additionally, they also need to be proficient enough to access the database server. This is one of the major reasons why it is deemed high impact and extremely severe.
SQL Injections- Categorized
As with everything else, SQL injection has some pre-defined categories as well. These are typically, the Classic and Blind SQLi models. These injections can be further categorized according to the methods applied to access backed data and the entire potential of damage.
In-band SQL
In this type of SQL injection, the cyber hacker uses a uniform and common channel to host their attack and access your data afterward. Because the process is fairly simple, a large number of cybercriminals try it.
In-band SQL attacks can be classified into further subcategories. In the following section, we will discuss all that and more.
Error-based attacks- If you are subject to an error-based attack it is probably because the cybercriminal has already tampered with your database leading to a series of error messages. The cybercriminal then uses the information from the same error messages to gain further details about the structure and type of your database.
Union-based- This is yet another unique method where your UNION SQL admin rights are misappropriated. For the uninitiated, these admin rights are crucial because any hacking or misappropriation can result in a combination of different catch-phrases that the attacker might try to use to gain HTTP responses. After a series of similar responses, they get the crucial information that can damage your company’s reputation.
Blind attacks- In this attack, the perpetrator will try to send multiple data volumes to your organization’s server. Next, it will observe the overall response from the system to gain more information about its overall structure. The method is deemed blind because data here cannot be directly sent from any databasespecific to a website, to the cybercriminal, which is why they do not have any details about the impending attack.
Because these attacks depend on the response from the server, they won’t be as easy to execute. Regardless, they are extremely harmful. Depending on the severity of the attack, you can also classify Blind attacks into multiple categories namely, Boolean and Time-based.
In the case of Boolean attacks, the perpetrator directly sends in SQL query or multiple SQL queries to your system database. This will prompt your application to send a result as a response and the result will depend on the authenticity of the query. After this point, the attacker can check the false results and collect the true results as well. This will allow them to access some amount of the data and tamper it at their will.
Time-based attacks are entirely different because here the attacker will first send an SQL query to the system database. Following this, the database will wait for a couple of seconds before rendering a response. Now, the perpetrator will check the timestamps of the database to figure out whether the queries they have sent are indeed true. They will then get an instant HTTP response or if they are using a waiting period, they will get the response following this period. This way, the attacker can understand whether the messages they had used were true without having to depend on the database-specific data.
Out-of-band SQLi
This type of attack is only successful when your database already has a couple of features that are accessible to the tool that the attackers are using. Typically, it is used instead of the former in-band attacks and deemed as an alternative.
The attacker will only perform the crime when they do not have the access to any channel for starting the attack or getting the user data. They may also launch it when your system servers are either slow or not stable enough for getting the actions performed. These collective methods depend on the overall severe capacity to come up with DNS and/or HTTP requests that may be used for data transfers. In the following section, we will delve deeper into the most common form of these injections.
Examples of SQL injections
Now that you have a basic idea about SQL attacks, lets learn more about SQL injections:
Example 1
Let us assume a shopping application that features multiple products that are further categorized. Every time, the user selects the �gifts’ option their browser will receive a pull request for the URL which is as follows:
Following this, the application will perform an SQL query to get the required details of the product from its system database.
SELECT * FROM products WHERE category = ‘Gifts’ AND released = 1
This SQL query will compel the database to return the following category:
all details (*)
from the products table
where the category is Gifts
and released is 1.
Here, 1 stands for the restriction that may be used to hide a couple of unreleased products. For the products that are released, the result would be 0.
In case this application is not as secure to have a solid defense against impending SQL attacks, the attacker and come up with the following query:
The resultant SQL query will be:
SELECT * FROM products WHERE category = ‘Gifts’–‘ AND released = 1
The important thing to understand here is the importance of the sentence with the double dash. It directly indicates SQL comments and also indicates that the remaining query can be read as a comment. Thanks to this, the rest of the query is easily removed, and it doesn’t include the previous results and instead displays 1. This gives them access to all products including the ones that are unreleased.
If the attacker types, this address: https://insecure-website.com/products?category=Gifts’+OR+1=1–they are likely to get the following result:
SELECT * FROM products WHERE category = ‘Gifts’ OR 1=1–‘ AND released = 1
This query will then return every existing item in every existing category of the application database.
Example 2
Let us assume an application allows its users to log in via their user credentials. In case, the user keys in ice as the username and cream as the password, the same application will assess these credentials by returning the following query:
SELECT * FROM users WHERE username = ‘ice’ AND password = ‘cream’
In case the query reveals the user details, the user gets to log in successfully, else they can’t.
When it comes to SQL attacks, the perpetrator can pretend to be a user and log in without having to use specific passwords. All they need to do is add an SQL comment sequence starting with �-‘ to get rid of the password from a specific part (namely, WHERE) of the query. For example, if your username is the administrator and the password is black you will get the following query:
SELECT * FROM users WHERE username = ‘administrator’–‘ AND password = ”
Following this, the query will return the entire username and the attacker can successfully log in as an existing new user.
To prevent such SQL injections, it is crucial to implement a solid strategy so that your company information is not misappropriated at any point. This is even more crucial if you are handling, third-part customer information. To be accountable, you need to create a solid threat modeling response so that you do not experience this situation at any point.
Remember, SQL attackers can get extremely sneaky and you never know when your system or database access is tampered with. That is why it is crucial to not just implement the right tools but also educate your employees about a quality threat modeling response. Host certificate courses and mandatory training if necessary. This will not just prevent an SQL injection attack as we discussed in our SQL injection example but it will also safeguard your data for the best. In the following section, we have recommended some of the ways you might want to prevent these attacks.
Example to prevent SQL injection attacks
Example 1
Of late, Rachel has been quite upset. Having joined a successful organization a while back, she had successfully transitioned into the new role. Her work was widely lauded for precision and accuracy until she made the negligent mistake of sharing confidential files over social media. Rachel was now under the flak of her seniors. Her colleague Jane, having understood the situation, considered discussing the matter in detail.
Jane: We all make mistakes, but you can always learn from them.
Rachel: But I’ve made the most negligent mistake. How can I undo this?
Jane: While you can’t �undo’ what you’ve already done, you can always focus on the present by taking the new DPP Certification.
Rachel: What is this DPP certification all about?
Jane: Well, this is the latest edition of the company that ensures you and other Employees and Contractors of the company Solutions understand and adhere to the best practices of information security and data processing concepts.
Rachel: Tell me more!
Jane: DPP has three primary modules focusing on the best practices while using social media, working from home, and handling client data. For social media, as you know at this point, it is advised to maintain and protect confidential client data. It is recommended that you safeguard your personal information while using social media accounts and refrain from sharing sensitive data on social media portals. The module also touches on some important concepts of online reputation management.
Rachel: This seems straightforward. What about the other modules like handling client data and working from home?
Jane: For working remotely, it is advised to use the dedicated VPN tunnel of XYZ and authenticate your device via their ABC Phone Application. This will ensure that the client data is safe and unexposed to potential threats. Finally, for client data protection, the module introduces you to industry best data security practices like storing data in their designated locations, not copying unauthorized parties on email, and making intelligent choices that prevent any form of infiltration by Malware or Phishing scams.
Rachel: Wow! This seems like an interesting module! I’ll take the DPP Certification.
A week later, Rachel took the DPP Certification, and right now she is aware of every vital Data Security Protocol.
Example 2
Jane: Hey! Why are you sitting in shade? It’s a beautiful day.
Matilda: I’m sitting in the shade because I don’t want anyone to see me. You see, I am not secure. I’m afraid that someone might hack me or I might get some virus.
Jane: It seems to me that you’re worried about surfing the web or using online applications. Don’t you use passwords? Don’t you connect through a VPN while working on office projects?
Matilda: What’s a VPN? I run all my applications for office and home on the same computer, and since I don’t change my passwords or have an antivirus, I am worried about clicking a suspicious link that might hang my computer. Maybe I won’t be able to reboot my computer then.
Jane: What? It’s not your ability to reboot that you should worry about; it’s your organization’s confidential data. Imagine if someone does hack you, tries to steal data from you, or you end up getting a virus like a Trojan or Malware. Something like this will cost your boss thousands or even millions of dollars. To make things worse, it might even cost your job.
Matilda: What? That sounds alarming! What should I do then?
Jane: While working from home, you should always connect to your company authorized VPN tunnel. Employees of our company, for instance, use a dedicated application called XYZ that generates highly-encrypted security codes which allows them to handle both internal and external workflows seamlessly. Additionally, you should also take precautions while using Social Media websites. Avoid sharing sensitive information via Social Media accounts and do not share confidential data with any unauthorized entity.
Jane: I can do that!
Matilda: And that is your first step to be �Secure’.
Example 3
Characters: Employee 1 (works at XYZ Solutions) and Employee 2 (works at ABC solutions)
Employee 1: Hey! Why do you look so upset?
Employee 2: Our company has called for a major layoff. One of my teammates accidentally fell prey to a Phishing scam. Not only did it lead to data misappropriation but our company also lost several thousands of dollars.
Employee 1: Whoa! Don’t you have any Data security protocol?
Employee 2: Nothing specific. Do you?
Employee 1: Of course we do. At XYZ Solutions, data security is taken extremely seriously. We always use a VPN, encrypted flash drives, and our private application for all office-related tasks. This doesn’t just secure our data but also prevents potential Phishing attacks and SQL injection Scams. Recently, our company introduced a DPP Certification Course. As an employee, we need to complete this certification to understand the concept of best practices in data security. This helps build awareness about data confidentiality which in turn protects us from data misappropriation of any degree. Finally, we also have a 24×7 Data Security Response Team who are always available to address data security concerns. In case of a potential attack, we inform our team immediately, who in turn, immediately address the security gap.
Employee 2: That’s impressive! Given the high standards of data security your company ensures, I’m confident that you’d never face a similar plight.
Employee 1: Yes, and our customers too can be assured that none of their confidential data is compromised.
Example 4
Characters: Computer 1 and Computer 2
Computer 1: Hey! You’re not sitting in the shade anymore. Is it because you’re secure now?
Computer 2: Of course, I am! Thanks to the Data Security Response Team of XYZ Solutions, I’m not afraid of data breaches anymore.
Computer 1: What does this team do?
Computer 2: Well, our Data Security Response team is always ready to handle security and data breach issues. Employees can alert the Team in the event of a possible data breach and the team will readily address their concerns, identifying and then bridging the data gaps. Since our team is available 24×7 to advise and respond to all data security queries, Employees can reach out to them any time.
Computer 2: Well, that’s impressive. But what about the XYZ Employees? How are they preventing potential data breaches?
Computer 1: XYZ Employees can take the DPP Core Certification Course to familiarize themselves with the best practices of information security.
Computer 2: What are these best practices?
Computer 1: It involves three primary modules. The first module focuses on the importance of using proper devices and networks ( VPNs, encrypted flash drives, and more), the second elucidates on the best social media and email practices, and the final module is about making smart decisions when it comes to handling sensitive client-specific information.
Computer 2: That seems like an all-encompassing Certification Course. I now understand why you’re so confident about your security standards.
Bottom Line
Now that you know all about SQL attacks, you will probably safeguard your system with the right tools to prevent such attacks. Remember, these attacks are getting common by the day and unless you create a solid threat modeling response, it is difficult to tackle them. This is regardless of the size or scale of your organization. If you are managing a business with an online website or an application, you need a solid threat-modeling response to prevent impending attacks. This will safeguard your data and prevent potential breaches.