OWASP: Top 10 CWE (Common Weakness Enumerations)

What is CWE (Common Weakness Enumerations)?

CWE, or Common Weakness Enumerations, is a community-developed list of common software security vulnerabilities. It is maintained by the MITRE Corporation and regularly updated by a group of international experts in software security.

The goal of CWE is to provide a standardized language for describing software security weaknesses. This makes it easier for developers and security professionals to communicate about vulnerabilities and their potential impact on software systems.

CWE is organized into categories based on the type of weakness, such as input validation errors or authentication and authorization issues. Within each category, there are specific weaknesses that fall under the umbrella of that category.

One of the most valuable aspects of CWE is that it is linked to other software security resources, such as the Common Vulnerability Scoring System (CVSS) and the Common Attack Pattern Enumeration and Classification (CAPEC). These linkages make it easier for developers and security professionals to understand the impact of specific weaknesses and how to mitigate them.

The OWASP Top 10 CWE list is a subset of the broader CWE list and focuses specifically on the most common and impactful vulnerabilities in web applications. This list is updated regularly and serves as a valuable resource for developers and security professionals looking to secure their web applications.

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

Improper Restriction of Operations within the Bounds of a Memory Buffer, also known as buffer overflow vulnerability, poses a significant security risk. This weakness occurs when a program writes data beyond the boundaries of a memory buffer, leading to memory corruption and potential code execution. Buffer overflow vulnerabilities can be exploited by malicious attackers to gain unauthorized access, inject malicious code, or cause system crashes. Implementing robust input validation and secure coding practices are crucial for mitigating the risks associated with CWE-119 and ensuring the integrity and security of software applications.

CWE-20: Improper Input Validation

Proper input validation is paramount for maintaining the security of software applications. CWE-20, also referred to as Improper Input Validation, highlights the risks associated with inadequate validation of user input. When input is not properly validated, various security vulnerabilities such as injection attacks, cross-site scripting (XSS), and other forms of code injection can arise. These vulnerabilities enable attackers to manipulate input data, leading to unauthorized access, data breaches, and potential compromise of sensitive information. By implementing robust input validation mechanisms, including strict input sanitization, input length checks, and the use of secure coding practices, developers can effectively mitigate the risks associated with CWE-20 and safeguard their applications from potential security breaches.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Improper Neutralization of Input During Web Page Generation, commonly known as Cross-site Scripting (XSS), is a critical security weakness that affects web applications. CWE-79 occurs when untrusted user input is not properly handled during the generation of web pages, allowing attackers to inject malicious scripts that can be executed by other users. XSS vulnerabilities enable attackers to steal sensitive information, hijack user sessions, deface websites, or launch phishing attacks. To mitigate the risks associated with CWE-79, web developers should employ proper input validation and implement output encoding techniques to ensure that user-supplied data is properly sanitized and rendered as plain text to prevent script execution.

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Improper Neutralization of Special Elements used in an OS Command, commonly referred to as OS Command Injection, is a severe security vulnerability that arises when untrusted user input is executed as part of a command by an operating system. CWE-78 allows attackers to manipulate command execution, leading to unauthorized access, data loss, or unintended execution of commands with elevated privileges. To mitigate the risks associated with OS Command Injection, developers should implement secure coding practices, such as validating and sanitizing user input, and employ parameterized queries or prepared statements when interacting with the operating system.
[Continued in the next paragraph.]

CWE-306: Missing Authentication for Critical Function

Missing Authentication for Critical Function is a significant vulnerability that occurs when authentication mechanisms are absent or improperly implemented for critical functions. CWE-306 enables unauthorized users to perform privileged actions or access sensitive data without proper authentication. This weakness can lead to unauthorized system access, data breaches, and the compromise of critical resources. Implementing robust authentication controls, including multi-factor authentication, session management, and access controls, is essential for mitigating the risks associated with CWE-306 and ensuring the integrity and security of software systems.

CWE-311: Missing Encryption of Sensitive Data

Missing Encryption of Sensitive Data is a critical security weakness that occurs when sensitive information is not adequately protected through encryption. CWE-311 leaves data vulnerable to unauthorized access or disclosure by malicious actors. This weakness can lead to severe consequences such as data breaches, identity theft, and privacy violations. To address the risks associated with CWE-311, it is essential to implement strong encryption algorithms and protocols to protect sensitive data both in transit and at rest. Employing secure key management practices, using encryption libraries or frameworks, and conducting regular security assessments are crucial steps in ensuring the confidentiality and integrity of sensitive information.

CWE-434: Unrestricted Upload of File with Dangerous Type

Unrestricted Upload of File with Dangerous Type, identified as CWE-434, poses a significant security risk for web applications. This weakness occurs when an application allows users to upload files without proper validation and control over file types. Attackers can exploit this vulnerability by uploading malicious files that can execute arbitrary code, overwrite critical files, or compromise the server's security. To mitigate the risks associated with CWE-434, developers should implement strict file validation mechanisms, including checking file extensions, performing content verification, and employing secure file storage practices. Additionally, implementing file type whitelisting and enforcing access controls can help prevent unauthorized execution of uploaded files and maintain the overall security of the application.

CWE-400: Uncontrolled Resource Consumption

Uncontrolled Resource Consumption, also known as resource management vulnerabilities, can lead to significant performance degradation and denial-of-service (DoS) attacks. CWE-400 arises when an application fails to properly manage system resources such as memory, file handles, or network connections. Attackers can exploit this weakness by exhausting resources, causing the application to become unresponsive or crash. To mitigate the risks associated with CWE-400, developers should implement resource usage limits, implement proper resource deallocation and cleanup procedures, and conduct thorough testing to ensure efficient resource allocation and prevent resource exhaustion attacks. Implementing robust resource management practices is essential for maintaining the availability and stability of software applications.

CWE-352: Cross-Site Request Forgery (CSRF)

Cross-Site Request Forgery (CSRF) is a significant vulnerability that can lead to unauthorized actions performed by authenticated users on a web application. CWE-352 occurs when an attacker tricks a user into executing unintended actions on a vulnerable website, exploiting the trust between the user and the application. CSRF attacks can result in unauthorized operations, data manipulation, and potential compromise of sensitive information. To mitigate the risks associated with CWE-352, developers should implement measures such as anti-CSRF tokens, strict validation of request origin, and secure session management. Additionally, user awareness and education about CSRF attacks can help prevent users from falling victim to such attacks and maintain the security of web applications.

CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

Improper Neutralization of Special Elements used in an SQL Command, commonly known as SQL Injection, is a critical vulnerability that affects web applications relying on database interactions. CWE-89 occurs when untrusted user input is concatenated into SQL queries without proper sanitization, enabling attackers to manipulate the queries' structure and execute unauthorized SQL commands. SQL Injection attacks can lead to data breaches, unauthorized access to databases, and potential exposure of sensitive information. To mitigate the risks associated with CWE-89, developers should implement parameterized queries or prepared statements, enforce proper input validation and sanitization, and employ secure coding practices. Regular security testing and code reviews can help identify and address potential SQL Injection vulnerabilities, ensuring the integrity and security of database-driven applications.

Conclusion

By incorporating secure coding practices, conducting regular security assessments, and staying updated on the latest security vulnerabilities and mitigation techniques, developers can effectively address the top 10 CWEs and enhance the overall security posture of their software applications.