Addressing 8 Critical Access Control Vulnerabilities

Access control vulnerabilities are one of the most common dangers in the complex realm of web application security. If neglected, these vulnerabilities have the potential to severely compromise the integrity and security of online applications. Vulnerabilities in access control greatly increase the risks to system and data availability, confidentiality, and integrity. Attackers may use them to alter data, obtain unauthorised access, steal confidential information, or interfere with system functions. Therefore, in order to successfully reduce these risks, organisations must adopt strong access control mechanisms and review and update their access control rules on a regular basis.

Vulnerabilities resulting from improper access control may appear as any of the following:

  • Unauthorized Access: An attacker finds a URL endpoint that, if improperly authenticated, grants access to private client information. Without first gaining authentication as a real user, the attacker can read or alter sensitive data by directly accessing this endpoint. Attacker provides a malicious file parameter../../../etc/passwd, they can read sensitive system files unauthorised.

By providing a malicious file parameter (../../../etc/passwd), the attacker can read sensitive system files unauthorized. This can lead to unauthorized disclosure of sensitive information, such as user credentials or system configuration details.

  • Force Browsing: Attackers can use force browsing, sometimes referred to as directory traversal or path traversal, to obtain files or directories that are not part of the intended directory structure by taking advantage of inadequate access constraints. Web applications that serve files dynamically from the server’s file system are usually the target of this attack. the attacker can access files or directories outside the intended directory structure. This can lead to unauthorized access to sensitive data, potentially compromising system security and confidentiality.

  • Privilege Escalation: An attacker with restricted user rights finds an application vulnerability that lets them escalate their privileges. For instance, they might obtain administrative access by taking advantage of a weakness in the user authentication procedure, giving them total control over the programme. If an attacker Bypass role editing the Json File view_admin_dashboard
  • Horizontal Privilege Escalation: An attacker uses a weakness in session management or access controls in a multi-tenant application environment to obtain access to the account of another user. Once inside, they have access to other users’ data that they can see or edit if they have the same privileges. Attacker Bypass role editing the Json File view_admin_dashboard(user_role=’regular_user’) the attacker can gain access to administrative features intended only for privileged users. This can result in unauthorized actions, such as modifying system settings or accessing sensitive information.
  • Vertical Privilege Escalation: When an attacker with ordinary user privileges finds a flaw, they can raise their privileges to administrator level. For example, they could take advantage of a weakness in the permission logic of the programme to obtain administrator access and carry out administrative tasks. Attacker Bypass role editing the Json File{ view_admin_dashboard(user_role=’Admin_user’)}, the attacker has the ability to get administrator privileges. This presents serious security issues since it gives them free access to sensitive data and administrative operations.
  • Data Leakage : When a web application neglects to appropriately implement access controls on a database query, an attacker can obtain private information that belongs to other users. The assailant creates a fraudulent query to obtain private data, like user credentials or bank details. Editing the get request on Json,

public UserProfile getUserProfile(int userId) {

    // Fetch user profile from the database

    return userRepository.findById(userId);


Private information belonging to other users can be obtained by the attacker. User security and privacy may be jeopardised if this results in the uninvited revelation of sensitive data, such as login passwords, private information, or financial information.

  • Data Manipulation: An attacker uses a flaw in access controls to obtain unauthorised access to a backend system or administrative interface. Once inside, they alter vital information including user profiles, product costs, or transaction histories, which can result in loss of money or harm to one’s reputation. Editing the request or using entity to retrieve the data. An attacker can obtain unauthorised access to administrative interfaces or backend systems by taking advantage of security holes in access controls or by retrieving data through entities. This gives them the ability to alter important data, such transaction history, product prices, and user profiles. This may lead to monetary loss, harm to one’s reputation, or interruption of commercial activities.
  • Cross-Site Request Forgery(CSRF): A logged-in user is tricked by an attacker into opening a compromised website or clicking on a malicious link that contains a forged request. Unknown to the user, this request causes the target website to perform a state-changing action (such as sending money or altering the user’s email address) because the user’s session is still active and permitted.

GET https://xyz.example/transfer?amount=100&destinationAccount=attackerAccount

By using faked requests to fool users that are signed in into altering their state, The attacker has the ability to change user data or execute unauthorised transactions. Financial loss, illegal account access, or the compromise of user accounts and private data are all possible outcomes of this.

Mitigating Access Control Vulnerabilities in Web Applications

The security and integrity of online applications are significantly jeopardised by flaws in access control. Mitigation techniques are essential for safeguarding sensitive data and preventing unwanted access. Here are a few practical methods for mitigating:

  • Principle of Least Privilege: Adhere to the principle of least privilege by only giving users the access they require to complete their tasks. Restrict authorised users’ access to sensitive resources and functionalities.
  • Robust Authentication Systems: To securely confirm user identification, utilise strong authentication methods like OAuth and multi-factor authentication (MFA). For further security, enforce strict password regulations and take into account biometric authentication.
  • Sturdy Authorization Structures: Make effective use of strong authorization frameworks to implement access control regulations. To manage user rights based on roles, attributes, or policies, use role-based access control (RBAC), attribute-based access control (ABAC), or policy-based access control (PBAC).
  • Sanitization and Validation of Input: To stop injection attacks (such as SQL injection and XSS), thoroughly validate and sanitise input. Verify and clean user inputs to make sure dangerous code is not included and that they follow expected formats.
  • Secure Session Management: Session hijacking and fixation attacks can be avoided by using secure session management procedures. To safeguard session data and guarantee session integrity, use encryption, secure tokens, and session expiration.
  • Audit Trails and Logging: Maintain thorough audit trails and logging systems in order to keep an eye on user behaviour and spot shady access attempts. Forensic analysis and compliance needs, record administrative actions, authentication events, and judgements about access control.