Difference between revisions of "Access Control Cheat Sheet"

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= DRAFT CHEAT SHEET - WORK IN PROGRESS =
 
 
=Introduction=
 
=Introduction=
  
This article is focused on providing clear, simple, actionable guidance for providing Access Control security in your applications.
+
This article is focused on providing clear, simple, actionable guidance for providing access control security in your applications. The objective is to provide guidance to developers, reviewers, designers, architects on designing, creating and maintaining access controls in web applications
  
 
==What is Access Control / Authorization?==
 
==What is Access Control / Authorization?==
  
Authorization is the process where requests to access a particular resource should be granted or denied. It should be noted that authorization is not equivalent to authentication - as these terms and their defininitions are frequently confused.
+
Authorization is the process where requests to access a particular resource should be granted or denied. It should be noted that authorization is not equivalent to authentication - as these terms and their definitions are frequently confused.  Authentication is providing and validating identity. Authorization includes the execution rules that determines what functionality and data the user (or Principal) may access, ensuring the proper allocation of access rights after authentication is successful.
  
Access Control is the method or mechanism of authorization to enfore that requests to a system resource or functionality should be granted.
+
Web applications need access controls to allow users (with varying privileges) to use the application. They also need administrators to manage the applications access control rules and the granting of permissions or entitlements to users and other entities. Various access control design methodologies are available. To choose the most appropriate one, a risk assessment needs to be performed to identify threats and vulnerabilities specific to your application, so that the proper access control methodology is appropriate for your application.
  
'''Role Based Access Control (RBAC)''' In Role-Based Access Control (RBAC), access decisions are based on an individual's roles and responsibilities within the organization or user base. The process of defining roles is usually based on analyzing the fundamental goals and structure of an organization and is usually linked to the security policy. For instance, in a medical organization, the different roles of users may include those such as doctor, nurse, attendant, nurse, patients, etc. Obviously, these members require different levels of access in order to perform their functions, but also the types of web transactions and their allowed context vary greatly depending on the security policy and any relevant regulations (HIPAA, Gramm-Leach-Bliley, etc.).
+
== Access Control Policy ==
  
An RBAC access control framework should provide web application security administrators with the ability to determine who can perform what actions, when, from where, in what order, and in some cases under what relational circumstances. http://csrc.nist.gov/rbac/ provides some great resources for RBAC implementation. The following aspects exhibit RBAC attributes to an access control model.
+
Why do we need an access control policy for web development?
*Roles are assigned based on organizational structure with emphasis on the organizational security policy
 
*Roles are assigned by the administrator based on relative relationships within the organization or user base. For instance, a manager would have certain authorized transactions over his employees. An administrator would have certain authorized transactions over his specific realm of duties (backup, account creation, etc.)
 
*Each role is designated a profile that includes all authorized commands, transactions, and allowable information access.
 
*Roles are granted permissions based on the principle of least privilege.
 
*Roles are determined with a separation of duties in mind so that a developer Role should not overlap a QA tester Role.
 
*Roles are activated statically and dynamically as appropriate to certain relational triggers (help desk queue, security alert, initiation of a new project, etc.)
 
*Roles can be only be transferred or delegated using strict sign-offs and procedures.
 
*Roles are managed centrally by a security administrator or project leader
 
 
  
'''Discretioinary Access Control (DAC)''' Discretionary Access Control (DAC) is a means of restricting access to information based on the identity of users and/or membership in certain groups. Access decisions are typically based on the authorizations granted to a user based on the credentials he presented at the time of authentication (user name, password, hardware/software token, etc.). In most typical DAC models, the owner of information or any resource is able to change its permissions at his discretion (thus the name). DAC has the drawback of the administrators not being able to centrally manage these permissions on files/information stored on the web server. A DAC access control model often exhibits one or more of the following attributes.
+
The intention of having an access control policy is to ensure that security requirements are described clearly to architects, designers, developers and support team, such that access control functionality is designed and implemented in a consistent manner.
*Data Owners can transfer ownership of information to other users
 
*Data Owners can determine the type of access given to other users (read, write, copy, etc.)
 
*Repetitive authorization failures to access the same resource or object generates an alarm and/or restricts the user's access
 
*Special add-on or plug-in software required to apply to an HTTP client to prevent indiscriminant copying by users ("cutting and pasting" of information)
 
*Users who do not have access to information should not be able to determine its characteristics (file size, file name, directory path, etc.)
 
*Access to information is determined based on authorizations to access control lists based on user identifier and group membership.
 
  
 +
= Role Based Access Control (RBAC) =
  
'''Mandatory Access Control (MAC)''' Mandatory Access Control (MAC) ensures that the enforcement of organizational security policy does not rely on voluntary web application user compliance. MAC secures information by assigning sensitivity labels on information and comparing this to the level of sensitivity a user is operating at. In general, MAC access control mechanisms are more secure than DAC yet have trade offs in performance and convenience to users. MAC mechanisms assign a security level to all information, assign a security clearance to each user, and ensure that all users only have access to that data for which they have a clearance. MAC is usually appropriate for extremely secure systems including multilevel secure military applications or mission critical data applications. A MAC access control model often exhibits one or more of the following attributes.
+
In Role-Based Access Control (RBAC), access decisions are based on an individual's roles and responsibilities within the organization or user base.  
*Only administrators, not data owners, make changes to a resource's security label.
 
*All data is assigned security level that reflects its relative sensitivity, confidentiality, and protection value.
 
*All users can read from a lower classification than the one they are granted (A "secret" user can read an unclassified document).
 
*All users can write to a higher classification (A "secret" user can post information to a Top Secret resource).
 
*All users are given read/write access to objects only of the same classification (a "secret" user can only read/write to a secret document).
 
*Access is authorized or restricted to objects based on the time of day depending on the labeling on the resource and the user's credentials (driven by policy).
 
*Access is authorized or restricted to objects based on the security characteristics of the HTTP client (e.g. SSL bit length, version information, originating IP address or domain, etc.)
 
  
 +
The process of defining roles is usually based on analyzing the fundamental goals and structure of an organization and is usually linked to the security policy. For instance, in a medical organization, the different roles of users may include those such as doctor, nurse, attendant, nurse, patients, etc. Obviously, these members require different levels of access in order to perform their functions, but also the types of web transactions and their allowed context vary greatly depending on the security policy and any relevant regulations (HIPAA, Gramm-Leach-Bliley, etc.).
  
=Attacks on Access Control=
+
An RBAC access control framework should provide web application security administrators with the ability to determine who can perform what actions, when, from where, in what order, and in some cases under what relational circumstances. 
  
Vertical Access Control Attacks - A standard user accessing administration functionality
+
The advantages of using this methodology are:
 
+
*Roles are assigned based on organizational structure with emphasis on the organizational security policy
Horizontal Access Control attacks - Same role, but accessing another user's private data
+
*Easy to use
 
+
*Easy to administer
Business Logic Access Control Attacks - Abuse of one or more linked activities that collectively realize a business objective
+
*Built into most frameworks
 
+
*Aligns with security principles like segregation of duties and least privileges
=Access Control Issues=
 
*Many applications used the "All or Nothing" approach - Once authenticated, all users have equal privileges
 
 
 
*Authorization Logic often relies on Security by Obscurity (STO) by assuming:
 
**Users will not find unlinked or hidden paths or functionality
 
**Users will not find and tamper with "obscured" client side parameters (i.e. "hidden" form fields, cookies, etc.)
 
 
*Applications with multiple permission levels/roles often increases the possibility of conflicting permission sets resulting in unanticipated privileges
 
 
 
*Many administrative interfaces require only a password for authentication
 
*Shared accounts combined with a lack of auditing and logging make it extremely difficult to differentiate between malicious and honest administrators
 
*Administrative interfaces are often not designed as “secure” as user-level interfaces given the assumption that administrators are trusted users
 
*Authorization/Access Control relies on client-side information (e.g., hidden fields)
 
*Web and application server processes run as root, Administrator, LOCALSYSTEM or other privileged accounts
 
*Some web applications access the database via sa or other administrative account (or more privileges than required)
 
*Some applications implement authorization controls by including a file or web control or code snippet on every page in the application
 
 
    <input type="text" name="fname" value="Derek">
 
    <input type="text" name="lname" value="Jeter">
 
    <input type="hidden" name="usertype" value="admin">
 
 
 
=Access Control Anti-Patterns=
 
 
 
*Hard-coded role checks in application code
 
*Lack of centralized access control logic
 
*Untrusted data driving access control decisions
 
*Access control that is "open by default"
 
*Lack of addressing horizontal access control in a standardized way (if at all)
 
*Access control logic that needs to be manually added to every endpoint in code
 
*non-anonymous entry point DO NOT have an access control check
 
*No authorization check at or near the beginning of code implementing sensitive activities
 
 
 
==Hard Coded Roles==
 
 
 
  if (user.isManager() ||
 
      user.isAdministrator() ||
 
      user.isEditor() ||
 
      user.isUser()) {
 
      //execute action
 
  }
 
 
 
'''Hard Codes Roles can create several issues including:'''
 
 
 
*Making the policy of an application difficult to "prove" for audit or Q/A purposes
 
*Causing new code to be pushed each time an access control policy needs to be changed.
 
*They are fragile and easy to make mistakes
 
 
 
==Order Specific Operations==
 
 
 
Imagine the following parameters
 
 
 
  http://example.com/buy?action=chooseDataPackage
 
  http://example.com/buy?action=customizePackage
 
  http://example.com/buy?action=makePayment
 
  http://example.com/buy?action=downloadData
 
 
 
'''Can an attacker control the sequence?'''
 
 
 
'''Can an attacker abuse this with concurency?'''
 
 
 
==Never Depend on Untrusted Data==
 
 
 
*Never trust user data for access control decisions
 
*Never make access control decisions in JavaScript
 
*Never depend on the order of values sent from the client
 
*Never make authorization decisions based solely on
 
**hidden fields
 
**cookie values
 
**form parameters
 
**URL parameters
 
**anything else from the request
 
 
 
 
=Attacking Access Controls=
 
 
 
*Elevation of privileges
 
*Disclosure of confidential data - Compromising admin-level accounts often result in access to a user's confidential data
 
*Data tampering - Privilege levels do not distinguish users who can only view data and users permitted to modify data
 
 
 
=Testing for Broken Access Control=
 
 
 
*Attempt to access administrative components or functions as an anonymous or regular user
 
**Scour HTML source for “interesting” hidden form fields
 
**Test web accessible directory structure for names like admin, administrator, manager, etc (i.e. attempt to directly browse to “restricted” areas)
 
*Determine how administrators are authenticated. Ensure that adequate authentication is used and enforced
 
*For each user role, ensure that only the appropriate pages or components are accessible for that role.
 
*Login as a low-level user, browse history for a higher level user’s cache, load the page to see if the original authorization is passed to a previous session.
 
*If able to compromise administrator-level account, test for all other common web application vulnerabilities (poor input validation, privileged database access, etc)
 
 
 
=Defenses Against Access Control Attacks=
 
 
 
*Implement role based access control to assign permissions to application users for vertical access control requirements
 
*Implement data-contextual access control to assign permissions to application users in the context of specific data items for horizontal access control requirements
 
*Avoid assigning permissions on a per-user basis
 
*Perform consistent authorization checking routines on all application pages
 
*Where applicable, apply DENY privileges last, issue ALLOW privileges on a case-by-case basis
 
*Where possible restrict administrator access to machines located on the local area network (i.e. it’s best to avoid remote administrator access from public facing access points)
 
*Log all failed access authorization requests to a secure location for review by administrators
 
*Perform reviews of failed login attempts on a periodic basis
 
*Utilize the strengths and functionality provided by the SSO solution you chose
 
 
 
'''Java'''
 
 
 
<pre>
 
 
 
if ( authenticated ) {
 
 
 
request.getSession(true).setValue(“AUTHLEVEL”) = X_USER;
 
 
 
}
 
 
 
</pre>
 
 
 
'''.NET (C#)'''
 
 
 
<pre>
 
 
 
if ( authenticated ) {
 
 
 
Session[“AUTHLEVEL”] = X_USER;
 
 
 
}
 
 
 
</pre>
 
 
 
 
 
'''PHP'''
 
 
 
<pre>
 
 
 
if ( authenticated ) {
 
 
 
$_SESSION[‘authlevel’] = X_USER; // X_USER is defined elsewhere as meaning, the user is authorized
 
 
 
}
 
 
 
</pre>
 
 
 
=Best Practices=
 
 
 
==Best Practice: Code to the Activity==
 
 
 
  if (AC.hasAccess(ARTICLE_EDIT)) {
 
      //execute activity
 
  }
 
*Code it once, never needs to change again
 
*Implies policy is persisted/centralized in some way
 
*Avoid assigning permissions on a per-user basis
 
*Requires more design/work up front to get right
 
 
 
==Best Practice: Centralized ACL Controller==
 
 
 
*Define a centralized access controller
 
      ACLService.isAuthorized(ACTION_CONSTANT)
 
      ACLService.assertAuthorized(ACTION_CONSTANT)
 
*Access control decisions go through these simple API’s
 
*Centralized logic to drive policy behavior and persistence
 
*May contain data-driven access control policy information
 
*Policy language needs to support ability to express both access rights and prohibitions
 
 
 
==Best Practice: Using a Centralized Access Controller==
 
 
 
*In Presentation Layer
 
  
      if (isAuthorized(VIEW_LOG_PANEL))
+
Problems that can be encountered while using this methodology:
      {
+
*Documentation of the roles and accesses has to be maintained stringently.
          Here are the logs
+
*Multi-tenancy can not be implemented effectively unless there is a way to associate the roles with multi-tenancy capability requirements e.g. OU in Active Directory
          <%=getLogs();%/>
+
*There is a tendency for scope creep to happen e.g. more accesses and privileges can be given than intended for. Or a user might be included in two roles if proper access reviews and subsequent revocation is not performed.
      }
+
*Does not support data based access control
 
*In Controller
 
  
      try (assertAuthorized(DELETE_USER))
+
The areas of caution while using RBAC are:
      {
+
*Roles must be only be transferred or delegated using strict sign-offs and procedures.
          deleteUser();
+
*When a user changes his role to another one, the administrator must make sure that the earlier access is revoked such that at any given point of time, a user is assigned to only those roles on a need to know basis.
      }
+
*Assurance for RBAC must be carried out using strict access control reviews.
  
==Best Practice: Verifying policy server-side==
+
= Discretionary Access Control (DAC) =
  
*Keep user identity verification in session
+
Discretionary Access Control (DAC) is a means of restricting access to information based on the identity of users and/or membership in certain groups. Access decisions are typically based on the authorizations granted to a user based on the credentials he presented at the time of authentication (user name, password, hardware/software token, etc.). In most typical DAC models, the owner of information or any resource is able to change its permissions at his discretion (thus the name).
*Load entitlements server side from trusted sources
 
*Force authorization checks on ALL requests
 
**JS file, image, AJAX and FLASH requests as well!
 
**Force this check using a filter if possible
 
  
=SQL Integrated Access Control=
+
A DAC framework can provide web application security administrators with the ability to implement fine grained access control. This model can be a basis for data based access control implementation
  
'''Example Feature'''
+
The advantages of using this model are:
 +
*Easy to use
 +
*Easy to administer
 +
*Aligns to the principle of least privileges.
 +
*Object owner has total control over access granted
  
    http://mail.example.com/viewMessage?msgid=2356342
+
Problems that can be encountered while using this methodology:
 +
*Documentation of the roles and accesses has to be maintained stringently.
 +
*Multi-tenancy can not be implemented effectively unless there is a way to associate the roles with multi-tenancy capability requirements e.g. OU in Active Directory
 +
*There is a tendency for scope creep to happen e.g. more accesses and privileges can be given than intended for.  
  
'''This SQL would be vulnerable to tampering'''
+
The areas of caution while using DAC are:
 +
*While granting trusts
  
  select * from messages where messageid = 2356342
+
*Assurance for DAC must be carried out using strict access control reviews.
  
'''Ensure the owner is referenced in the query!'''
+
= Mandatory Access Control (MAC) =
  
  select * from messages where messageid = 2356342 AND messages.message_owner =
+
Mandatory Access Control (MAC) ensures that the enforcement of organizational security policy does not rely on voluntary web application user compliance. MAC secures information by assigning sensitivity labels on information and comparing this to the level of sensitivity a user is operating at. MAC is usually appropriate for extremely secure systems including multilevel secure military applications or mission critical data applications.  
  
=Access Control Positive Patterns=
+
The advantages of using this methodology are:
 +
* Access to an object is based on the sensitivity of the object
 +
* Access based on need to know is strictly adhered to and scope creep has minimal possibility
 +
* Only an administrator can grant access
  
*Code to the activity, not the role
+
Problems that can be encountered while using this methodology:
*Centralize access control logic
+
* Difficult and expensive to implement
*Design access control as a filter
+
* Not agile
*Deny by default, fail securely
 
*Build centralized access control mechanism
 
*Apply same core logic to presentation and server-side access control decisions
 
*Determine access control through Server-side trusted data
 
  
=Data Contextual Access Control=
+
The areas of caution while using MAC are:
 +
* Classification and sensitivity assignment at an appropriate and pragmatic level
 +
* Assurance for MAC must be carried out to ensure that the classification of the objects is at the appropriate level.
  
'''Data Contextual / Horizontal Access Control API examples'''
+
= Permission Based Access Control =
  
    ACLService.isAuthorized(EDIT_ORG, 142)
+
The key concept in Permission Based Access Control is the abstraction of application actions into a set of ''permissions''. A ''permission'' may be represented simply as a string based name, for example "READ". Access decisions are made by checking if the current user ''has'' the permission associated with the requested application action.  
    ACLService.assertAuthorized(VIEW_ORG, 900)
 
  
Long Form
+
The ''has'' relationship between the user and permission may be satisfied by creating a direct relationship between the user and permission (called a ''grant''), or an indirect one. In the indirect model the permission ''grant'' is to an intermediate entity such as ''user group''. A user is considered a member of a ''user group'' if and only if the user ''inherits'' permissions from the ''user group''. The indirect model makes it easier to manage the permissions for a large number of users, since changing the permissions assigned to the user group affects all members of the user group.
  
    isAuthorized(user, EDIT_ORG, Organization.class, 14)
+
In some Permission Based Access Control systems that provide fine-grained domain object level access control, permissions may be grouped into ''classes''. In this model it is assumed that each domain object in the system can be associated with a ''class'' which determines the permissions applicable to the respective domain object. In such a system a "DOCUMENT" class may be defined with the permissions "READ", "WRITE" and DELETE"; a "SERVER" class may be defined with the permissions "START", "STOP", and "REBOOT".
 
*Essentially checking if the user has the right role in the context of a specific object
 
*Centralize access control logic
 
*Protecting data at the lowest level!
 
  
=Authors and Primary Editors=
+
= Authors and Primary Editors =
  
Jim Manico - jim [at] owasp dot org
+
Shruti Kulkarni - shruti.kulkarni [at] owasp.org<br/>
Fred Donovan - fred.donovan [at] owasp dot org
+
Adinath Raveendra Raj - adinath [at] acciente.com<br/>
Mennouchi Islam Azeddine - azeddine.mennouchi [at] owasp.org
+
Mennouchi Islam Azeddine - azeddine.mennouchi [at] owasp.org<br/>
 +
Jim Manico - jim [at] owasp.org<br/>
  
== Other Cheatsheets ==
+
= Other Cheatsheets =
{{Cheatsheet_Navigation}}
+
{{Cheatsheet_Navigation_Body}}
  
 +
__NOTOC__ <headertabs />
 
[[Category:Cheatsheets]]
 
[[Category:Cheatsheets]]

Latest revision as of 13:38, 6 March 2016

This article is focused on providing clear, simple, actionable guidance for providing access control security in your applications. The objective is to provide guidance to developers, reviewers, designers, architects on designing, creating and maintaining access controls in web applications

What is Access Control / Authorization?

Authorization is the process where requests to access a particular resource should be granted or denied. It should be noted that authorization is not equivalent to authentication - as these terms and their definitions are frequently confused. Authentication is providing and validating identity. Authorization includes the execution rules that determines what functionality and data the user (or Principal) may access, ensuring the proper allocation of access rights after authentication is successful.

Web applications need access controls to allow users (with varying privileges) to use the application. They also need administrators to manage the applications access control rules and the granting of permissions or entitlements to users and other entities. Various access control design methodologies are available. To choose the most appropriate one, a risk assessment needs to be performed to identify threats and vulnerabilities specific to your application, so that the proper access control methodology is appropriate for your application.

Access Control Policy

Why do we need an access control policy for web development?

The intention of having an access control policy is to ensure that security requirements are described clearly to architects, designers, developers and support team, such that access control functionality is designed and implemented in a consistent manner.

In Role-Based Access Control (RBAC), access decisions are based on an individual's roles and responsibilities within the organization or user base.

The process of defining roles is usually based on analyzing the fundamental goals and structure of an organization and is usually linked to the security policy. For instance, in a medical organization, the different roles of users may include those such as doctor, nurse, attendant, nurse, patients, etc. Obviously, these members require different levels of access in order to perform their functions, but also the types of web transactions and their allowed context vary greatly depending on the security policy and any relevant regulations (HIPAA, Gramm-Leach-Bliley, etc.).

An RBAC access control framework should provide web application security administrators with the ability to determine who can perform what actions, when, from where, in what order, and in some cases under what relational circumstances.

The advantages of using this methodology are:

  • Roles are assigned based on organizational structure with emphasis on the organizational security policy
  • Easy to use
  • Easy to administer
  • Built into most frameworks
  • Aligns with security principles like segregation of duties and least privileges

Problems that can be encountered while using this methodology:

  • Documentation of the roles and accesses has to be maintained stringently.
  • Multi-tenancy can not be implemented effectively unless there is a way to associate the roles with multi-tenancy capability requirements e.g. OU in Active Directory
  • There is a tendency for scope creep to happen e.g. more accesses and privileges can be given than intended for. Or a user might be included in two roles if proper access reviews and subsequent revocation is not performed.
  • Does not support data based access control

The areas of caution while using RBAC are:

  • Roles must be only be transferred or delegated using strict sign-offs and procedures.
  • When a user changes his role to another one, the administrator must make sure that the earlier access is revoked such that at any given point of time, a user is assigned to only those roles on a need to know basis.
  • Assurance for RBAC must be carried out using strict access control reviews.

Discretionary Access Control (DAC) is a means of restricting access to information based on the identity of users and/or membership in certain groups. Access decisions are typically based on the authorizations granted to a user based on the credentials he presented at the time of authentication (user name, password, hardware/software token, etc.). In most typical DAC models, the owner of information or any resource is able to change its permissions at his discretion (thus the name).

A DAC framework can provide web application security administrators with the ability to implement fine grained access control. This model can be a basis for data based access control implementation

The advantages of using this model are:

  • Easy to use
  • Easy to administer
  • Aligns to the principle of least privileges.
  • Object owner has total control over access granted

Problems that can be encountered while using this methodology:

  • Documentation of the roles and accesses has to be maintained stringently.
  • Multi-tenancy can not be implemented effectively unless there is a way to associate the roles with multi-tenancy capability requirements e.g. OU in Active Directory
  • There is a tendency for scope creep to happen e.g. more accesses and privileges can be given than intended for.

The areas of caution while using DAC are:

  • While granting trusts
  • Assurance for DAC must be carried out using strict access control reviews.

Mandatory Access Control (MAC) ensures that the enforcement of organizational security policy does not rely on voluntary web application user compliance. MAC secures information by assigning sensitivity labels on information and comparing this to the level of sensitivity a user is operating at. MAC is usually appropriate for extremely secure systems including multilevel secure military applications or mission critical data applications.

The advantages of using this methodology are:

  • Access to an object is based on the sensitivity of the object
  • Access based on need to know is strictly adhered to and scope creep has minimal possibility
  • Only an administrator can grant access

Problems that can be encountered while using this methodology:

  • Difficult and expensive to implement
  • Not agile

The areas of caution while using MAC are:

  • Classification and sensitivity assignment at an appropriate and pragmatic level
  • Assurance for MAC must be carried out to ensure that the classification of the objects is at the appropriate level.

The key concept in Permission Based Access Control is the abstraction of application actions into a set of permissions. A permission may be represented simply as a string based name, for example "READ". Access decisions are made by checking if the current user has the permission associated with the requested application action.

The has relationship between the user and permission may be satisfied by creating a direct relationship between the user and permission (called a grant), or an indirect one. In the indirect model the permission grant is to an intermediate entity such as user group. A user is considered a member of a user group if and only if the user inherits permissions from the user group. The indirect model makes it easier to manage the permissions for a large number of users, since changing the permissions assigned to the user group affects all members of the user group.

In some Permission Based Access Control systems that provide fine-grained domain object level access control, permissions may be grouped into classes. In this model it is assumed that each domain object in the system can be associated with a class which determines the permissions applicable to the respective domain object. In such a system a "DOCUMENT" class may be defined with the permissions "READ", "WRITE" and DELETE"; a "SERVER" class may be defined with the permissions "START", "STOP", and "REBOOT".

Shruti Kulkarni - shruti.kulkarni [at] owasp.org
Adinath Raveendra Raj - adinath [at] acciente.com
Mennouchi Islam Azeddine - azeddine.mennouchi [at] owasp.org
Jim Manico - jim [at] owasp.org