The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

Primary

Architecture and Design
OMISSION: This weakness is caused by missing a security tactic during the architecture and design phase.

Architecture and Design
Developers sometimes perform authentication at the primary channel, but open up a secondary channel that is assumed to be private. For example, a login mechanism may be listening on one network port, but after successful authentication, it may open up a second port where it waits for the connection, but avoids authentication because it assumes that only the authenticated party will connect to the port.

Operation
When migrating data to the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), there is a risk of losing the protections that were originally provided by hosting on internal networks. If access does not require authentication, it can be easier for attackers to access the data from anywhere on the Internet.

High

Access Control
Other
Gain Privileges or Assume Identity
Varies by Context
Exposing critical functionality essentially provides an attacker with the privilege level of that functionality. The consequences will depend on the associated functionality, but they can range from reading or modifying sensitive data, accessing administrative or other privileged functionality, or possibly even executing arbitrary code.

Manual Analysis

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 authentication mechanisms.

These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.

Automated Static Analysis

Automated static analysis is useful for detecting commonly-used idioms for authentication. A tool may be able to analyze related configuration files, such as .htaccess in Apache web servers, or detect the usage of commonly-used authentication libraries.
Generally, automated static analysis tools have difficulty detecting custom authentication schemes. In addition, the software's design may include some functionality that is accessible to any user and does not require an established identity; an automated technique that detects the absence of authentication may report false positives.

Limited

Manual Static Analysis - Binary or Bytecode

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

SOAR Partial

Dynamic Analysis with Automated Results Interpretation

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

SOAR Partial

Dynamic Analysis with Manual Results Interpretation

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

SOAR Partial

Manual Static Analysis - Source Code

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)

SOAR Partial

Automated Static Analysis - Source Code

According to SOAR [REF-1479], the following detection techniques may be useful:

Cost effective for partial coverage:

Source code Weakness Analyzer
Context-configured Source Code Weakness Analyzer

SOAR Partial

Architecture or Design Review

According to SOAR [REF-1479], the following detection techniques may be useful:

Highly cost effective:

Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.)
Formal Methods / Correct-By-Construction

Cost effective for partial coverage:

Attack Modeling

High

Architecture and Design

Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability.
Identify all potential communication channels, or other means of interaction with the software, to ensure that all channels are appropriately protected, including those channels that are assumed to be accessible only by authorized parties. Developers sometimes perform authentication at the primary channel, but open up a secondary channel that is assumed to be private. For example, a login mechanism may be listening on one network port, but after successful authentication, it may open up a second port where it waits for the connection, but avoids authentication because it assumes that only the authenticated party will connect to the port.
In general, if the software or protocol allows a single session or user state to persist across multiple connections or channels, authentication and appropriate credential management need to be used throughout.

Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Architecture and Design

Where possible, avoid implementing custom, "grow-your-own" authentication routines and consider using authentication capabilities as provided by the surrounding framework, operating system, or environment. These capabilities may avoid common weaknesses that are unique to authentication; support automatic auditing and tracking; and make it easier to provide a clear separation between authentication tasks and authorization tasks.
In environments such as the World Wide Web, the line between authentication and authorization is sometimes blurred. If custom authentication routines are required instead of those provided by the server, then these routines must be applied to every single page, since these pages could be requested directly.

Architecture and Design
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 libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator [REF-45].

Implementation
System Configuration
Operation
When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data [REF-1297] [REF-1298] [REF-1302].

In the following Java example the method createBankAccount is used to create a BankAccount object for a bank management application.

public BankAccount createBankAccount(String accountNumber, String accountType,String accountName, String accountSSN, double balance) {

BankAccount account = new BankAccount();account.setAccountNumber(accountNumber);account.setAccountType(accountType);account.setAccountOwnerName(accountName);account.setAccountOwnerSSN(accountSSN);account.setBalance(balance);
return account;
}

However, there is no authentication mechanism to ensure that the user creating this bank account object has the authority to create new bank accounts. Some authentication mechanisms should be used to verify that the user has the authority to create bank account objects.
The following Java code includes a boolean variable and method for authenticating a user. If the user has not been authenticated then the createBankAccount will not create the bank account object.

private boolean isUserAuthentic = false;

// authenticate user,

// if user is authenticated then set variable to true

// otherwise set variable to false
public boolean authenticateUser(String username, String password) {...}
public BankAccount createNewBankAccount(String accountNumber, String accountType,String accountName, String accountSSN, double balance) {
BankAccount account = null;
if (isUserAuthentic) {account = new BankAccount();account.setAccountNumber(accountNumber);account.setAccountType(accountType);account.setAccountOwnerName(accountName);account.setAccountOwnerSSN(accountSSN);account.setBalance(balance);}return account;
}

In 2022, the OT:ICEFALL study examined products by 10 different Operational Technology (OT) vendors. The researchers reported 56 vulnerabilities and said that the products were "insecure by design" [REF-1283]. If exploited, these vulnerabilities often allowed adversaries to change how the products operated, ranging from denial of service to changing the code that the products executed. Since these products were often used in industries such as power, electrical, water, and others, there could even be safety implications.
Multiple vendors did not use any authentication for critical functionality in their OT products.

In 2021, a web site operated by PeopleGIS stored data of US municipalities in Amazon Web Service (AWS) Simple Storage Service (S3) buckets.

A security researcher found 86 S3 buckets that could be accessed without authentication (CWE-306) and stored data unencrypted (CWE-312). These buckets exposed over 1000 GB of data and 1.6 million files including physical addresses, phone numbers, tax documents, pictures of driver's license IDs, etc. [REF-1296] [REF-1295]

While it was not publicly disclosed how the data was protected after discovery, multiple options could have been considered.

The sensitive information could have been protected by ensuring that the buckets did not have public read access, e.g., by enabling the s3-account-level-public-access-blocks-periodic rule to Block Public Access. In addition, the data could have been encrypted at rest using the appropriate S3 settings, e.g., by enabling server-side encryption using the s3-bucket-server-side-encryption-enabled setting. Other settings are available to further prevent bucket data from being leaked. [REF-1297]

CVE-2024-11680
File-sharing PHP product does not check if user is logged in during requests for PHP library files under an includes/ directory, allowing configuration changes, code execution, and other impacts.
https://www.cve.org/CVERecord?id=CVE-2024-11680

CVE-2022-31260
Chain: a digital asset management program has an undisclosed backdoor in the legacy version of a PHP script (CWE-912) that could allow an unauthenticated user to export metadata (CWE-306)
https://www.cve.org/CVERecord?id=CVE-2022-31260

CVE-2022-29951
TCP-based protocol in Programmable Logic Controller (PLC) has no authentication.
https://www.cve.org/CVERecord?id=CVE-2022-29951

CVE-2022-29952
Condition Monitor firmware uses a protocol that does not require authentication.
https://www.cve.org/CVERecord?id=CVE-2022-29952

CVE-2022-30276
SCADA-based protocol for bridging WAN and LAN traffic has no authentication.
https://www.cve.org/CVERecord?id=CVE-2022-30276

CVE-2022-30313
Safety Instrumented System uses proprietary TCP protocols with no authentication.
https://www.cve.org/CVERecord?id=CVE-2022-30313

CVE-2022-30317
Distributed Control System (DCS) uses a protocol that has no authentication.
https://www.cve.org/CVERecord?id=CVE-2022-30317

CVE-2021-21972
Chain: Cloud computing virtualization platform does not require authentication for upload of a tar format file (CWE-306), then uses .. path traversal sequences (CWE-23) in the file to access unexpected files, as exploited in the wild per CISA KEV.
https://www.cve.org/CVERecord?id=CVE-2021-21972

CVE-2020-10263
Bluetooth speaker does not require authentication for the debug functionality on the UART port, allowing root shell access
https://www.cve.org/CVERecord?id=CVE-2020-10263

CVE-2021-23147
WiFi router does not require authentication for its UART port, allowing adversaries with physical access to execute commands as root
https://www.cve.org/CVERecord?id=CVE-2021-23147

CVE-2021-37415
IT management product does not perform authentication for some REST API requests, as exploited in the wild per CISA KEV.
https://www.cve.org/CVERecord?id=CVE-2021-37415

CVE-2020-13927
Default setting in workflow management product allows all API requests without authentication, as exploited in the wild per CISA KEV.
https://www.cve.org/CVERecord?id=CVE-2020-13927

CVE-2002-1810
MFV. Access TFTP server without authentication and obtain configuration file with sensitive plaintext information.
https://www.cve.org/CVERecord?id=CVE-2002-1810

CVE-2008-6827
Agent software running at privileges does not authenticate incoming requests over an unprotected channel, allowing a Shatter" attack.
https://www.cve.org/CVERecord?id=CVE-2008-6827

CVE-2004-0213
Product enforces restrictions through a GUI but not through privileged APIs.
https://www.cve.org/CVERecord?id=CVE-2004-0213

CVE-2020-15483
monitor device allows access to physical UART debug port without authentication
https://www.cve.org/CVERecord?id=CVE-2020-15483

CVE-2019-9201
Programmable Logic Controller (PLC) does not have an authentication feature on its communication protocols.
https://www.cve.org/CVERecord?id=CVE-2019-9201

No Authentication for Critical Function

SFP31
Missing authentication

Part 4-2
Req CR 1.1

Part 4-2
Req CR 1.2

Part 4-2
Req CR 2.1

Part 4-1
Req SR-2

Part 4-1
Req SVV-3

Allowed
This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

PLOVER
2006-07-19
Draft 3
2006-07-19

Eric Dalci
Cigital
2008-07-01
updated Time_of_Introduction

CWE Content Team
MITRE
2008-09-08
updated Relationships, Relationship_Notes, Taxonomy_Mappings

CWE Content Team
MITRE
2010-02-16
updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Detection_Factors, Likelihood_of_Exploit, Name, Observed_Examples, Potential_Mitigations, References, Related_Attack_Patterns, Relationships

CWE Content Team
MITRE
2010-06-21
updated Common_Consequences, Potential_Mitigations, References

CWE Content Team
MITRE
2011-06-01
updated Common_Consequences

CWE Content Team
MITRE
2011-06-27
updated Relationships

CWE Content Team
MITRE
2011-09-13
updated Potential_Mitigations, References, Relationships

CWE Content Team
MITRE
2012-05-11
updated Potential_Mitigations, Relationships

CWE Content Team
MITRE
2012-10-30
updated Potential_Mitigations

CWE Content Team
MITRE
2014-07-30
updated Detection_Factors, Relationships, Taxonomy_Mappings

CWE Content Team
MITRE
2015-12-07
updated Relationships

CWE Content Team
MITRE
2017-11-08
updated Likelihood_of_Exploit, Modes_of_Introduction, References, Relationships

CWE Content Team
MITRE
2019-01-03
updated Related_Attack_Patterns

CWE Content Team
MITRE
2019-06-20
updated Related_Attack_Patterns, Type

CWE Content Team
MITRE
2020-02-24
updated Relationships

CWE Content Team
MITRE
2020-08-20
updated Relationships

CWE Content Team
MITRE
2021-07-20
updated Observed_Examples, Relationships

CWE Content Team
MITRE
2021-10-28
updated Relationships

CWE Content Team
MITRE
2022-06-28
updated Observed_Examples, Relationships

CWE Content Team
MITRE
2022-10-13
updated Applicable_Platforms, Demonstrative_Examples, Description, Observed_Examples, Potential_Mitigations, References, Relationship_Notes, Relationships

CWE Content Team
MITRE
2023-01-31
updated Related_Attack_Patterns, Relationships

CWE Content Team
MITRE
2023-04-27
updated References, Relationships, Taxonomy_Mappings

CWE Content Team
MITRE
2023-06-29
updated Mapping_Notes, Relationships

CWE Content Team
MITRE
2023-10-26
updated Observed_Examples

CWE Content Team
MITRE
2024-02-29
4.14
2024-02-29
updated Observed_Examples

CWE Content Team
MITRE
2024-07-16
4.15
2024-07-16
updated Common_Consequences, Description, Diagram, Modes_of_Introduction, Potential_Mitigations, Time_of_Introduction

CWE Content Team
MITRE
2024-11-19
4.16
2024-11-19
updated Relationships

CWE Content Team
MITRE
2025-04-03
4.17
2025-04-03
updated Observed_Examples

CWE Content Team
MITRE
2025-09-09
4.18
2025-09-09
updated Detection_Factors, References

CWE Content Team
MITRE
2025-12-11
4.19
2025-12-11
updated Relationships, Weakness_Ordinalities

"Mapping CWE to 62443" Sub-Working Group
CWE-CAPEC ICS/OT SIG
2023-04-25
Suggested mappings to ISA/IEC 62443.

Abhi Balakrishnan
2024-02-29
4.15
2024-07-16
Provided diagram to improve CWE usability

No Authentication for Critical Function