What is Web Application Security? | Attacks & Best Practices | EC-Council

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What Is a Web Application?

Web Applications, or web apps, are computer applications built on the client-server model. They utilize web browsers to facilitate end-users to seamlessly conduct activities over the internet. Any website element that delivers a service or task for users can be called a web app. Some common web application examples include webmail, e-commerce sites, online calculators, and online banking. Web applications are developed and built through browsers that support code languages such as HTML5, JavaScript, CSS, etc. Some of the widely used application servers include ASP.NET, ASP, PHP, and JSP. In addition, three components are required for a web app to run

  • A web server responsible for managing client requests
  • An application server accountable for completing tasks
  • A database to store the required information

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What Are Web Application Attacks?

Security aspects may often be overlooked in the web application development process, leading to higher chances of vulnerabilities and web attacks. Attackers take advantage of these security flaws by infiltrating the application to further their malicious intent. While numerous measures and protocols are established, such as SSL certificates and firewalls, to keep confidential data safe, attackers can still find a way around them to bypass security measures and exploit the application to access personal and sensitive data.

What Are Web Application Attacks?

Some of the common web application attacks include:

  • Cross-site Scripting (XXS)
  • SQL Injection
  • DDoS Attack
  • Directory Traversal Attacks
  • Brute Force Attack
  • Man-in-the-Middle Attack
  • Local File Injection
  • Broken Authentication
  • Security Misconfiguration
  • XML External Entity (XXE)
  • Insecure Deserialization

What Is Web Application Security?

What Is Web Application Security?

Web application security, better known as WebAppSec, focuses on safeguarding websites and digital services from malicious attackers. It encompasses tools, techniques, and guidelines to strengthen defenses against web application attacks and improve the application’s security posture. Web app penetration testing or hacking techniques must be applied at the development stage to identify vulnerabilities and determine the overall security of the web application architecture. Additionally, organizations should conduct web application security training to equip developers with security foundations and tools to stay ahead of attacks.

Web Application Security Best Practices

Web application security is an essential aspect that must be prioritized and updated to protect the application against new and existing threats. Implementing security standards and safe practices are crucial to ensuring the overall protection of confidential and personal data. By deploying appropriate web app security strategies, one can:

  • Prevent attackers from accessing sensitive information/data.
  • Minimize losses that occurred due to poor security standards.
  • Detect vulnerabilities and other threat factors early on, thus resulting in minimal or no damage.
  • Establish compliance standards to enhance client credibility and attract partners, shareholders, and prospective investors.

Organizations can hire web application security professionals or web application penetration testers to review and update security techniques and strategies. Conducting a vulnerability assessment using the same methods attackers use to exploit web applications is the most effective way to uncover security gaps in the web application infrastructure. This enables security professionals to analyze vulnerabilities and other loopholes in a web application. Additionally, based on the findings and the threat level, the vulnerabilities are classified along with methods that can be used to eliminate them. After identifying and classifying vulnerabilities, security strategies and policies can be incorporated to eradicate them. Four security testing methods are implemented based on the situation and organizational aspects:

Dynamic Application Security Test (DAST)

This test is carried out for web applications at minimal risk of being exploited by an attacker.

Static Application Security Test (SAST)

SAST consists of automated and manual testing methodologies. It is the best testing method for identifying bugs without having the need to run applications in real-time. In addition, it allows developers and designers to filter and eliminate vulnerabilities present in the source code.

Penetration Test (Pen Test)

Penetration Testing is ideal for checking the quality of crucial applications which undergo constant, significant changes.

Runtime Application Self Protection (RASP)

Numerous technologies are combined with filtering and blocking attacks or threats in real-time to eliminate critical vulnerabilities or threat factors. It allows developers to discover threats within their application network.

Critical Skills of a Web Application Security Tester/Expert

Web Application Scanning

Web applications and websites are the primary targets of attackers since they are inherently more difficult to defend than traditional applications. This is due to numerous factors, including third-party apps, improper coding, and public access, among others. Attackers can easily take advantage of existing web application architecture security due to these exploitable issues.

Web Application Scanning

Network Scanning

Network Scanning

Web application security professionals should be well versed in scanning the network channel for assessing vulnerabilities and ensure that there are no open ports that can be violated by a third party or used to spoof an application. Network scanning also includes:

  • Examining the vulnerabilities in the channel used to communicate or transfer information.
  • Checking the connection between the web application or website to the webserver.
  • Using tools to locate malicious IP addresses in the list.


Cryptography skills are vital since it involves creating and analyzing protocols that prevent malicious third parties from accessing information shared between two entities. Cryptography methods help to anticipate weak encryptions and analyze how a criminal attempts to breach an organization’s security walls. A Web Application Hacker must be familiar with digital signatures, several types of ciphers, hash algorithms, and other cryptography principles and techniques such as symmetric cryptography and public-key cryptography


Grip on AST

Grip on AST

Application Security Testing (AST) is carried out in source code to detect vulnerabilities and weak links to make the application’s security more robust. A web application security professional must have in-depth knowledge of the various AST tools and expertise to incorporate them into the web application development lifecycle.

Staying Updated

Web application security professionals are required to stay up to date on the recent technological advancements. In addition, they must be aware of the existing and new application attacks and how to ethically hack an application to conduct vulnerability assessment and audits.

Web application security professionals

Exploring Web Application Security Checklist (OWASP Top 10) 2021

Ethical Hackers and Penetration Testers can use penetration testing tools and techniques to identify vulnerabilities by following specific practices and methods that can later be patched to eliminate an attack. A standard web application security checklist should include the threats following the latest draft of the OWASP Top 10 2021 framework.

Broken Access Control

Most web applications are programmed to check permissions before displaying data in the user interface. Without verification, broken access control happens where attackers spoof the request to access and misuse data.

Cryptographic Failures

This risk category highlights data breaches, sensitive data exposure, and other vulnerabilities arising due to cryptographic failures.


All data is stored in unique databases. The requests to keep the data are built-in queries written in a Structured Query Language – SQL. All applications use SQL queries to edit and read the data. The injection is a vulnerability that occurs due to insufficient validation of user data. The attacker can exploit this issue to access the place where data is stored.

Insecure Design

This new risk category is introduced in the OWASP 2021 owing to the growing issues and risks highlighted by application security professionals due to design flaws in web applications that are a significant concern.

Security Misconfiguration

Misconfigured app-security issues can range from poor configuration codes in the development phase to misconfigured faults in pre-features and functions, all of which can add to the expanding list of vulnerabilities. Several attacks can be mitigated by modifying the default settings when installing a CMS. Because of this, a misconfiguration can happen at any point, including:

  • Network services
  • Platform webserver
  • Application server
  • Database frameworks
  • Custom code
  • Pre-installed virtual machines
  • Container’s storage

Vulnerable and Outdated Components

Application researchers find this new addition to the OWASP framework challenging as security risks arise from vulnerable and dated components. It was earlier known as “Components with Known Vulnerabilities.” Application security is at stake when the software is outdated or unsupported or can arise from third-party elements that create dependencies. These third-party components or frameworks make dependencies that malicious actors can easily exploit. It can cause considerable damage and lead to the loss of data and essential documents. The best solution to avoid this is by regularly updating the third-party tools and uninstalling the ones that have not been updated in a long time.

Identification and Authentication Failures

Earlier known as Broken Authentication, this risk category now includes weaknesses and vulnerabilities mapped to identification failures. Authentication of users to defend against outsider attacks or impersonation is crucial to web application security. There are chances of authentication errors if applications allow automated attacks like credential stuffing, brute force attacks, accepts weak or commonly used passwords etc

Software and Data Integrity Failures

This new category involves issues related to software updates, critical data, and elements that lead to integrity failure. It is associated with poor codes and infrastructure, which cannot provide adequate security against integrity violations. According to CVE/CVSS data analysis, this category has significantly impacted the threat landscape for application security.

Security Logging and Monitoring Failures

Renamed from the previous title of “insufficient logging & monitoring,” this risk category can lead to severe attacks from all quarters and pose a severe security and risk assessment challenge. Security logging and monitoring are essential to identify and mitigate active data breaches, which are impossible if there is insufficient logging and monitoring.

Server-Side Request Forgery

This new risk category resides at the tenth position of the OWASP framework 2021 and has a relatively low incidence rate. While SSRF flaws are common because of the migration to cloud-based servers, they are increasing steadily. SSRF vulnerabilities arise when applications fail to detect or validate a user-supplied URL, which an attacker can exploit by sending an HTTP request to a domain of their choice.

How Can WAHS Help You Become a Skilled Web Application Security Expert?

  • Learn, hack, test, and secure web applications from existing and emerging security threats in the industry verticals through challenges derived from EC-Council’s iLabs environments – from C|EH certification to C|PENT and beyond.
  • You can directly move to the advanced training course of C|PENT (Certified Penetration Testing Professional).
  • Gain mastery of the WAHS program and earn a recognized certification from EC-Council – the pioneer of the C|EH program and many others
  • Push your limits and test your hacking skills through Capture-The-Flag competitions offered in this web application security training.
  • Get a better grasp of WAHS with 100% practical learning and acquire job-ready skills.
  • You can test your skills on your own or follow the tutor’s instructions. Solve complex challenges and reach the goal with comprehensive training to develop web application security skills and techniques using basic and advanced tools
  • Get an edge over your peers with WAHS certification, which paves the way for professionals to learn Advanced Web Application Penetration.

Level Up with Web Application Hacking & Security

‘Break the Code’ challenge is for ethical hacking beginners and professionals who want to test their skills against various levels of threats. The difficulties of the challenge increase with each level. Similar challenges are available on different platforms, but only a handful will win you rewards, increasing your chances of being at the top of the list.

With the Web Application Hacking and Security program, you can put your abilities to the test and learn how to hack apps and secure web applications. The WAHS course is ideal for everyone, whether you are a beginner or a seasoned ethical hacker. Each section of the challenge pushes you to test your skills as you encounter SQL Injection, Security Misconfigurations, Cross-site Scripting, and various other concepts through which you need to hack your way. With WAHS, you also get to learn Advanced Web Application Penetration Testing, Advanced SQL Injection, XSS, Network Scanning, etc. The web application security certification is for people in charge of implementing, administering, or safeguarding online applications. If you are a cyber or IT expert interested in learning or proposing mitigation strategies for various online security concerns and want a pure hands-on curriculum, this is the course you have been waiting for.

The Web Application Hacking and Security exam assesses the candidates’ ability to conduct a web application security assessment in a demanding real-world situation. Candidates who achieve a score of more than 60% will receive the Web Application Security Associate certification, those who earn a score of more than 75% will receive the Certified Web Application Security Professional, and those who achieve a score of more than 90% will be awarded the Certified Web Application Security Expert certification.

Average Salary and Career Outlook

Penetration tester salaries range from $57,000 to $134,000, depending on the IT security analyst’s experience level. Salary ranges are determined by various factors, including educational qualifications, certifications, and expertise in the field. An application security analyst assesses application security, and other software is reviewed to determine how data may be made safer.

Which Roles Can Benefit from Web Application Hacking and Security (WAHS) Course?

  • Penetration Tester
  • Ethical Hacker
  • Web Application Penetration
  • Tester/Security Engineer
  • Auditor
  • Red Team Engineer
  • Information Security Engineer
  • Risk/Vulnerability Analyst
  • Vulnerability Manager
  • Incident responder

Web Application Security Tester/Analyst/Professional Responsibilities include:

  • Working with clients to know their test requirements.
  • Planning and implementing penetration testing techniques, tools, and procedures.
  • Performing remote or physical security testing on a client’s network or infrastructure to detect security flaws.
  • Scanning open ports using tools and techniques.
  • Using social engineering methodologies to bypass security.
  • Penetrating systems security to assess application vulnerability.
  • Advising on mitigating system security concerns.
  • Reporting findings, risks, and conclusions to the management and other decision-makers.

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Course Outline

Advanced Web Application Penetration Testing

Web application penetration testing is the practice of detecting vulnerabilities in a web application using penetration testing methods and tools. The main goal of web application penetration testing is to find security flaws or threats throughout the application and its components. It is also helpful in prioritizing the identified vulnerabilities and devising proper mitigation strategies based on this result.

Advanced SQL Injection (SQLi)

SQL Injection permits an attacker to access data that they would generally be unable to recover. This data may comprise a few items, such as private details about a client, sensitive company data, or user lists. Most of the significant data breaches that occur today have been the outcomes of an SQL Injection attack, and it takes a massive hit on an organization’s finances and reputation.

Reflected, Stored, and DOM-based Cross-Site Scripting (XSS)

There are three types of cross-site scripting, which are as follows:

  • Stored XSS: Also known as persistent XSS or second-order XSS, it occurs when a malicious script/code is directly injected/executed in a vulnerable web application or stored on the target server. It is highly damaging when compared to the reflected XSS attack.
  • Reflected XSS: Reflected XSS, also known as the non-persistent XSS, occurs when a vulnerable web application returns an unvalidated input or error message from the user’s web browser. This includes a part of the complete input by the user containing the malicious code. Upon clicking, the attacker gains unauthorized access and exploits the user’s confidential data for malicious intent.
  • Dom-based XSS: Document Object Model (DOM) based XSS occurs when a vulnerability is entered/found in the DOM instead of the HTML body. Attackers can manipulate these vulnerabilities to execute malicious code to gain unauthorized access to the victim’s system or access their confidential data.

Cross-Site Request Forgery (CSRF) – GET and POST Methods:

A Cross-site request forgery is also referred to as XSRF. It is an attack that targets authenticated users and leverages this web vulnerability to exploit an authenticated user’s trust in a web application. The process of fetching data from a third-party website is known as a Cross-Site Request. Cross-Site Request Forgery occurs when a cybercriminal copies the layout, design, or website format from where data is being pulled. The attacks can be executed using two methods — GET and the POST method.

  • Get Method
    In the GET method, the user simply clicks on the forged link to find the fake webpage. This website executes a script that sends an unsolicited request. Upon execution, confidential information is accessible by the attacker.
  • POST Method
    It is similar to the GET method, but the only exception is that POST methods are delivered using the form tags. When maliciously inserted into a form, the attacker can view the user’s confidential data by clicking the submit button.

Server-Side Request Forgery (SSRF)

It is a type of attack that compromises a server by sending requests to web applications that target internal systems behind a firewall. The attacker may misuse the server’s capacity to read or edit internal resources. By selecting the URLs, an attacker can read the server configuration like AWS metadata, connect it to interior services such as HTTP-enabled databases, perform post requests towards internally non-exposed services, or modify the URLs. The attacker can also select the URL destination of their choice.

Security Misconfiguration

Security measures that are poorly configured, leaving the systems and data at risk, are security misconfigurations. It usually implies that the configuration settings do not meet the security standards necessary for preserving security and reducing organizational risks. It is a critical web app risk that could lead to application misconfigurations attacks.

Directory Browsing/ Brute Forcing

A brute-force or browsing attack is a trial-and-error exhaustive search technique to guess a possible combination of passwords till the desired result is achieved. Attackers use this trial-and-error strategy to decode encrypted data, such as passwords. A brute force attack may take time; it may be challenging to carry out if measures like data stuffing are employed and sometimes impossible.

CMS Vulnerability Scanning

The CMS vulnerability scanner scans the entire CMS for possible risks and examines the details of the target system with the information of the recent attacks available from the database. It maintains the database to alert the current risks and then analyses the systems to avoid new risks.

Network Scanning

Network scanning is crucial for assessing security and system maintenance. Gathering information that enables identifying all the active hosts on the network and mapping them to their IP addresses defines network scanning in a nutshell. Web application security is important to prevent data web application attacks. A web application firewall can mitigate and nip numerous application-layer attacks in the bud. Without a proper web app security strategy and tools in place, cybercriminals can easily leverage web app vulnerabilities to launch malware campaigns and steal sensitive data.

Auth Bypass

Authentication bypass is a vulnerability when unauthorized users gain access to application resources without authorization.

Web App Enumeration

Attackers use the web application enumeration technique to implement brute force methods into guessing and confirming valid users in a system. It exploits a web application with a user authentication process set up and breaks the process by guessing the user credentials.

Dictionary Attack

A dictionary attack is a brute force technique where a different combination of words and phrases are entered to break into a password-protected system, network, or resource. Moreover, it can similarly be used to decode a key while decrypting a secret message.

Insecure Direct Object Reference Prevention (IDOR)

Insecure Direct Object Reference Prevention is the security concern that arises when an application offers direct access to confidential or high privileged resources, accessible only by a few authorized users via user inputs that are not validated. This allows an attacker to infiltrate the system and access confidential data without authorization or authentication.

Broken Access Control

Broken Access Control is a web application vulnerability that enables unauthorized users to access systems, networks, and resources, giving them advanced privileges. Access control flaws are a frequent occurrence in the absence of automated detection or adequate testing.

Local File Inclusion (LFI)

The Local File Inclusion attack results from poorly scripted web applications that allow a web application to input or upload files on the webserver, allowing an attacker to read, modify, or execute files on the victim’s system. An attacker can bypass security and access confidential information on the server or misconfigure it due to this file inclusion vulnerability. LFI leads to data loss or theft, remote code execution, or Cross-Site Scripting (XSS). Attackers uploading malicious files can disrupt the functioning of websites, web applications, and web servers.

Remote File Inclusion (RFI)

Poorly written web applications and a lack of appropriate security protocols lead to vulnerabilities like Remote File Inclusion. In an RFI attack, malicious hackers exploit these loopholes by running malicious code from a remote file or file from an external source on the target system. An attacker uses this vulnerability to upload remote files containing malware, leading to content modification, website takes over, or data theft.

Arbitrary File Download

Some web applications or web browsers allow the option for viewing or downloading files on your server. If this is not restricted or the input is not scrutinized, threat actors can send malicious requests or download critical or sensitive files from your server. Attackers can download arbitrary files from the system via directory traversal attacks if the input is not correctly filtered before being utilized to obtain files from the file cabinet or extract attachments from a received message.

Arbitrary File Upload

Arbitrary File Upload is a vulnerability that occurs when a file type is not verified or filtered before being uploaded to a web application. The most significant risk associated with these types of flaws is that an attacker might upload and execute a malicious PHP, ASP, or another script file and control the target’s system to run commands.

Using Components with Known Vulnerabilities

Most applications are prone to attack because unsecured, unsupported, or outdated vulnerable components are easy targets for threat actors to exploit. Sometimes, most developers are not aware of all the versions of the components or how many elements need to be patched or updated.

Command Injection

Command Injection vulnerability exploits a vulnerable web application to run arbitrary commands on a host operating system, primarily because of inadequate input validation. The vulnerability allows an attacker to utilize a web application’s privileges to execute commands on the operating system and get unauthorized access to the operating system as a whole and make edits.

Remote Code Execution

The act or process which allows an attacker to execute malicious code on a remote system over LAN, WAN, or the internet is known as remote code execution and access system-level privileges. In simple words, executing an arbitrary code over the network is considered a remote code execution.

File Tampering

The process of intentionally altering the data in a file via unauthorized or unethical means is known as file tampering. The file can be changed, deleted, modified, or replaced with a new file or a malicious file, which, when executed, could cause possible damage to the system.

Privilege Escalation

Privilege Escalation is the act or the process in which an attacker exploits a bug, weak link, design flaw, or vulnerability in the configuration of a system to gain privileged access to various resources and confidential data that are only accessible to higher authorities or system administrators.

Log Poisoning

The attacker injects malicious input into the log server to obtain a reverse shell via the Local File Inclusion vulnerability. Attackers upload malware-infested files and fake entries to corrupt the log files. Modifying log files through log poisoning can be used to cover up the digital footprints after a cyberattack or data breach.

Weak SSL Ciphers

Weak SSL ciphers are coded algorithms that use a key that is small in length. Executing weak SSL ciphers increases the possibility of a broken encryption scheme. Consequently, it results in low-security standards, which the attacker could easily exploit.

Cookie Modification

Cookie modification, also known as cookie poisoning, is the act of manipulating or imitating a cookie. This helps the attacker infiltrate security measures and send fake/incorrect information to the server to gain unauthorized access to the user’s/victim’s account.

Source Code Analysis

Source code analysis tools are crucial to grasp the structure of the code and analyze the application behavior. These tools aid in automated testing and static or dynamic testing of source codes to debug them. It can be a source code of a computer application, software applications etc., and is done before it is incorporated. This helps ensure the software’s security standards and does not possess potentially exploitable vulnerabilities that can compromise the system.

Session Fixation

Session Fixation is an application attack that allows an attacker to hijack a valid user session by deceiving the target user. This type of attack is implemented on an established session via the victim’s browser to exploit the flaws and other vulnerabilities. The attack starts before the user has logged in, wherein the attacker obtains the session ID and then hijacks the session.


It is a type of attack which deceives the user into clicking a malicious web page element that executes the malicious code and gives the attacker unauthorized access to the user’s system or account to view confidential data.

HTTP Request Header Modification

It is the process of modifying the HTTP headers which results in the execution of malicious code. HTTP headers are used for the communication/exchange of additional information between the client and server via the request and response header. Inserting malicious code in the response header can result in the execution of the malicious code. As a result, the attacker can view the user’s confidential data or gain unauthorized access to the system/data.

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