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Improper Authorization

Draft Class
Structure: Simple
Description

This vulnerability occurs when an application fails to properly verify whether a user has permission to access specific data or perform certain actions before allowing the request.

Extended Description

Authorization is the security gatekeeper that decides what an authenticated user is allowed to do. It checks a user's privileges against defined permissions before granting access to resources like files, database records, or administrative functions. When this check is missing, inconsistent, or flawed, the gate is left open. Failing to enforce proper authorization can have severe consequences. Attackers or regular users may exploit this weakness to view sensitive data they shouldn't see, modify or delete critical information, disrupt services for others, or even execute unauthorized commands. This makes improper authorization a root cause for data breaches, system compromise, and privilege escalation attacks.
Common Consequences 3
Scope: Confidentiality

Impact: Read Application DataRead Files or Directories

An attacker could read sensitive data, either by reading the data directly from a data store that is not properly restricted, or by accessing insufficiently-protected, privileged functionality to read the data.

Scope: Integrity

Impact: Modify Application DataModify Files or Directories

An attacker could modify sensitive data, either by writing the data directly to a data store that is not properly restricted, or by accessing insufficiently-protected, privileged functionality to write the data.

Scope: Access Control

Impact: Gain Privileges or Assume Identity

An attacker could gain privileges by modifying or reading critical data directly, or by accessing insufficiently-protected, privileged functionality.
Detection Methods 9
Automated Static AnalysisLimited
Automated static analysis is useful for detecting commonly-used idioms for authorization. A tool may be able to analyze related configuration files, such as .htaccess in Apache web servers, or detect the usage of commonly-used authorization libraries. Generally, automated static analysis tools have difficulty detecting custom authorization schemes. In addition, the software's design may include some functionality that is accessible to any user and does not require an authorization check; an automated technique that detects the absence of authorization may report false positives.
Automated Dynamic Analysis
Automated dynamic analysis may find many or all possible interfaces that do not require authorization, but manual analysis is required to determine if the lack of authorization violates business logic
Manual AnalysisModerate
This weakness can be detected using tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session. Specifically, manual static analysis is useful for evaluating the correctness of custom authorization mechanisms.
Manual Static Analysis - Binary or BytecodeSOAR Partial
According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Binary / Bytecode disassembler - then use manual analysis for vulnerabilities & anomalies
Dynamic Analysis with Automated Results InterpretationSOAR Partial
According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Web Application Scanner Web Services Scanner Database Scanners
Dynamic Analysis with Manual Results InterpretationSOAR Partial
According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Host Application Interface Scanner Fuzz Tester Framework-based Fuzzer Forced Path Execution Monitored Virtual Environment - run potentially malicious code in sandbox / wrapper / virtual machine, see if it does anything suspicious
Manual Static Analysis - Source CodeSOAR Partial
According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Focused Manual Spotcheck - Focused manual analysis of source Manual Source Code Review (not inspections)
Automated Static Analysis - Source CodeSOAR Partial
According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Context-configured Source Code Weakness Analyzer
Architecture or Design ReviewHigh
According to SOAR [REF-1479], the following detection techniques may be useful: ``` Highly cost effective: ``` Formal Methods / Correct-By-Construction ``` Cost effective for partial coverage: ``` Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.)
Potential Mitigations 5
Phase: Architecture and Design
Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
Phase: Architecture and Design
Ensure that you perform access control checks related to your business logic. These checks may be different than the access control checks that you apply to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
Phase: Architecture and Design

Strategy: Libraries or Frameworks

Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
Phase: Architecture and Design
For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page. One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.
Phase: System ConfigurationInstallation
Use the access control capabilities of your operating system and server environment and define your access control lists accordingly. Use a "default deny" policy when defining these ACLs.
Demonstrative Examples 2

ID : DX-95

This function runs an arbitrary SQL query on a given database, returning the result of the query.

Code Example:

Bad
PHP
php

//Use a prepared statement to avoid CWE-89* $preparedStatement = $globalDbHandle->prepare('SELECT * FROM employees WHERE name = :name'); $preparedStatement->execute(array(':name' => $name)); return $preparedStatement->fetchAll();}

php
While this code is careful to avoid SQL Injection, the function does not confirm the user sending the query is authorized to do so. An attacker may be able to obtain sensitive employee information from the database.

ID : DX-96

The following program could be part of a bulletin board system that allows users to send private messages to each other. This program intends to authenticate the user before deciding whether a private message should be displayed. Assume that LookupMessageObject() ensures that the $id argument is numeric, constructs a filename based on that id, and reads the message details from that file. Also assume that the program stores all private messages for all users in the same directory.

Code Example:

Bad
Perl
perl

For purposes of this example, assume that CWE-309 and*

perl
While the program properly exits if authentication fails, it does not ensure that the message is addressed to the user. As a result, an authenticated attacker could provide any arbitrary identifier and read private messages that were intended for other users.
One way to avoid this problem would be to ensure that the "to" field in the message object matches the username of the authenticated user.
  
Observed Examples 20
CVE-2022-24730Go-based continuous deployment product does not check that a user has certain privileges to update or create an app, allowing adversaries to read sensitive repository information
CVE-2009-3168Web application does not restrict access to admin scripts, allowing authenticated users to reset administrative passwords.
CVE-2009-2960Web application does not restrict access to admin scripts, allowing authenticated users to modify passwords of other users.
CVE-2009-3597Web application stores database file under the web root with insufficient access control (Storage of File with Sensitive Data Under Web Root), allowing direct request.
CVE-2009-2282Terminal server does not check authorization for guest access.
CVE-2009-3230Database server does not use appropriate privileges for certain sensitive operations.
CVE-2009-2213Gateway uses default "Allow" configuration for its authorization settings.
CVE-2009-0034Chain: product does not properly interpret a configuration option for a system group, allowing users to gain privileges.
CVE-2008-6123Chain: SNMP product does not properly parse a configuration option for which hosts are allowed to connect, allowing unauthorized IP addresses to connect.
CVE-2008-5027System monitoring software allows users to bypass authorization by creating custom forms.
CVE-2008-7109Chain: reliance on client-side security (Client-Side Enforcement of Server-Side Security) allows attackers to bypass authorization using a custom client.
CVE-2008-3424Chain: product does not properly handle wildcards in an authorization policy list, allowing unintended access.
CVE-2009-3781Content management system does not check access permissions for private files, allowing others to view those files.
CVE-2008-4577ACL-based protection mechanism treats negative access rights as if they are positive, allowing bypass of intended restrictions.
CVE-2008-6548Product does not check the ACL of a page accessed using an "include" directive, allowing attackers to read unauthorized files.
CVE-2007-2925Default ACL list for a DNS server does not set certain ACLs, allowing unauthorized DNS queries.
CVE-2006-6679Product relies on the X-Forwarded-For HTTP header for authorization, allowing unintended access by spoofing the header.
CVE-2005-3623OS kernel does not check for a certain privilege before setting ACLs for files.
CVE-2005-2801Chain: file-system code performs an incorrect comparison (Incorrect Comparison), preventing default ACLs from being properly applied.
CVE-2001-1155Chain: product does not properly check the result of a reverse DNS lookup because of operator precedence (Operator Precedence Logic Error), allowing bypass of DNS-based access restrictions.
  
References 9
Seven Pernicious Kingdoms: A Taxonomy of Software Security Errors
Katrina Tsipenyuk, Brian Chess, and Gary McGraw
NIST Workshop on Software Security Assurance Tools Techniques and Metrics • NIST
07-11-2005
https://samate.nist.gov/SSATTM_Content/papers/Seven%20Pernicious%20Kingdoms%20-%20Taxonomy%20of%20Sw%20Security%20Errors%20-%20Tsipenyuk%20-%20Chess%20-%20McGraw.pdf
ID: REF-6
Role Based Access Control and Role Based Security
NIST
https://csrc.nist.gov/projects/role-based-access-control(2023-04-07)
ID: REF-229
Writing Secure Code
Michael Howard and David LeBlanc
Microsoft Press
04-12-2002
https://www.microsoftpressstore.com/store/writing-secure-code-9780735617223
ID: REF-7
Top 25 Series - Rank 5 - Improper Access Control (Authorization)
Frank Kim
SANS Software Security Institute
04-03-2010
https://www.sans.org/blog/top-25-series-rank-5-improper-access-control-authorization(2023-04-07)
ID: REF-231
OWASP Enterprise Security API (ESAPI) Project
OWASP
https://owasp.org/www-project-enterprise-security-api/(2025-07-24)
ID: REF-45
Authentication using JAAS
Rahul Bhattacharjee
https://javaranch.com/journal/2008/04/authentication-using-JAAS.html(2023-04-07)
ID: REF-233
The Art of Software Security Assessment
Mark Dowd, John McDonald, and Justin Schuh
Addison Wesley
2006
ID: REF-62
The Art of Software Security Assessment
Mark Dowd, John McDonald, and Justin Schuh
Addison Wesley
2006
ID: REF-62
State-of-the-Art Resources (SOAR) for Software Vulnerability Detection, Test, and Evaluation
Gregory Larsen, E. Kenneth Hong Fong, David A. Wheeler, and Rama S. Moorthy
07-2014
https://www.ida.org/-/media/feature/publications/s/st/stateoftheart-resources-soar-for-software-vulnerability-detection-test-and-evaluation/p-5061.ashx(2025-09-05)
ID: REF-1479
 
  
  
 
 
Likelihood of Exploit 
 
 
 
 High 
 
 
  
 
 
Applicable Platforms 
 
 
 
 
 
Languages:
 
 
 Not Language-Specific : Undetermined 
 
 
Technologies:
 
 
 Web Server : OftenDatabase Server : Often 
 
 
 
  
 
 
Modes of Introduction 
 
 
 
 
 
  Implementation  
 
  Architecture and Design  
 
  Operation  
 
 
 
  
Related Attack Patterns 
  
Alternate Terms 
AuthZ
"AuthZ" is typically used as an abbreviation of "authorization" within the web application security community. It is distinct from "AuthN" (or, sometimes, "AuthC") which is an abbreviation of "authentication." The use of "Auth" as an abbreviation is discouraged, since it could be used for either authentication or authorization.
      
 
 
Related Weaknesses 
 
 
 
 
  ChildOf:
 Improper Access Control (CWE-284) 
  ChildOf:
 Improper Access Control (CWE-284) 
 
 
 
 
Taxonomy Mapping 
  • 7 Pernicious Kingdoms
  • OWASP Top Ten 2007
  • OWASP Top Ten 2004
  • Software Fault Patterns