Incorrect Authorization

Incomplete Class
Structure: Simple
Description

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Common Consequences 5
Scope: Confidentiality

Impact: Read Application DataRead Files or Directories

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

Scope: Integrity

Impact: Modify Application DataModify Files or Directories

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

Scope: Access Control

Impact: Gain Privileges or Assume IdentityBypass Protection Mechanism

An attacker could bypass intended access restrictions to gain privileges by modifying or reading critical data directly, or by accessing privileged functionality.

Scope: ConfidentialityIntegrityAvailability

Impact: Execute Unauthorized Code or Commands

An attacker could use elevated privileges to execute unauthorized commands or code.

Scope: Availability

Impact: DoS: Crash, Exit, or RestartDoS: Resource Consumption (CPU)DoS: Resource Consumption (Memory)DoS: Resource Consumption (Other)

An attacker could gain unauthorized access to resources on the system and excessively consume those resources, leading to a denial of service.

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. Even if they can be customized to recognize these schemes, they might not be able to tell whether the scheme correctly performs the authorization in a way that cannot be bypassed or subverted by an attacker.
Automated Dynamic Analysis
Automated dynamic analysis may not be able to find interfaces that are protected by authorization checks, even if those checks contain weaknesses.
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) [REF-229] 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 access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied 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 [REF-7].
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 1
The following code could be for a medical records application. It displays a record to already authenticated users, confirming the user's authorization using a value stored in a cookie.

Code Example:

Bad
PHP
php
The programmer expects that the cookie will only be set when getRole() succeeds. The programmer even diligently specifies a 2-hour expiration for the cookie. However, the attacker can easily set the "role" cookie to the value "Reader". As a result, the $role variable is "Reader", and getRole() is never invoked. The attacker has bypassed the authorization system.
Observed Examples 13
CVE-2025-24839collaboration platform allows attacker to access an AI bot by using a plugin to set a critical property
CVE-2025-32796LLM application development platform allows non-admin users to enable or disable apps using certain API endpoints
CVE-2021-39155Chain: A microservice integration and management platform compares the hostname in the HTTP Host header in a case-sensitive way (Improper Handling of Case Sensitivity, Improper Validation of Unsafe Equivalence in Input), allowing bypass of the authorization policy (Incorrect Authorization) using a hostname with mixed case or other variations.
CVE-2019-15900Chain: sscanf() call is used to check if a username and group exists, but the return value of sscanf() call is not checked (Unchecked Return Value), causing an uninitialized variable to be checked (Use of Uninitialized Variable), returning success to allow authorization bypass for executing a privileged (Incorrect Authorization).
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-2008-7109Chain: 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-2008-4577ACL-based protection mechanism treats negative access rights as if they are positive, allowing bypass of intended restrictions.
CVE-2006-6679Product relies on the X-Forwarded-For HTTP header for authorization, allowing unintended access by spoofing the header.
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 7
Role Based Access Control and Role Based Security
NIST
ID: REF-229
Writing Secure Code
Michael Howard and David LeBlanc
Microsoft Press
04-12-2002
ID: REF-7
Top 25 Series - Rank 5 - Improper Access Control (Authorization)
Frank Kim
SANS Software Security Institute
04-03-2010
ID: REF-231
Authentication using JAAS
Rahul Bhattacharjee
ID: REF-233
OWASP Enterprise Security API (ESAPI) Project
OWASP
ID: REF-45
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
ID: REF-1479
Likelihood of Exploit

High

Applicable Platforms
Languages:
Not Language-Specific : Undetermined
Technologies:
Web Server : OftenDatabase Server : Often
Modes of Introduction
Architecture and Design
Implementation
Operation
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.
Taxonomy Mapping
  • ISA/IEC 62443
  • ISA/IEC 62443
  • ISA/IEC 62443
  • ISA/IEC 62443
  • ISA/IEC 62443
  • ISA/IEC 62443
  • ISA/IEC 62443
  • ISA/IEC 62443
Notes
Terminology Assuming a user with a given identity, authorization is the process of determining whether that user can access a given resource, based on the user's privileges and any permissions or other access-control specifications that apply to the resource.