CWE-106: Struts: Plug-in Framework not in Use

Définition

What is CWE-106?

This weakness occurs when a Java application, particularly one using the Struts framework, does not implement a structured input validation plugin like the Struts Validator. Skipping this framework forces developers to write custom validation logic, which is often error-prone and increases the risk of security flaws from improperly handled user input.

Without a dedicated validation framework, your application becomes vulnerable to common web attacks. Unchecked user input is a primary entry point for cross-site scripting (XSS), SQL injection, and unauthorized command execution, as attackers can inject malicious code or manipulate application logic. While Java environments typically avoid memory corruption issues, the risk extends to integrated native code. If your J2EE application passes unvalidated data to native libraries or components that lack proper bounds checking, a simple input validation oversight can escalate into a severe buffer overflow attack, compromising the entire system.

Impact réel

Real-world CVEs caused by CWE-106

Aucune référence CVE publique n'est liée à ce CWE dans le catalogue MITRE pour le moment.

Comment les attaquants l'exploitent

Parcours de l'attaquant étape par étape

1
In the following Java example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for an online business site. The user will enter registration data and, through the Struts framework, the RegistrationForm bean will maintain the user data.
2
However, the RegistrationForm class extends the Struts ActionForm class which does use the Struts validator plug-in to provide validator capabilities. In the following example, the RegistrationForm Java class extends the ValidatorForm and Struts configuration XML file, struts-config.xml, instructs the application to use the Struts validator plug-in.
3
The plug-in tag of the Struts configuration XML file includes the name of the validator plug-in to be used and includes a set-property tag to instruct the application to use the file, validator-rules.xml, for default validation rules and the file, validation.XML, for custom validation.

Exemple de code vulnérable

Vulnerable Java

In the following Java example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for an online business site. The user will enter registration data and, through the Struts framework, the RegistrationForm bean will maintain the user data.

Vulnérable Java

public class RegistrationForm extends org.apache.struts.action.ActionForm {
```
// private variables for registration form* 
  	private String name;
  	private String email;
  	...
  	
  	public RegistrationForm() {
  	```
  		super();
  	}
```
// getter and setter methods for private variables* 
  	...
  	}

Exemple de code sécurisé

Secure Java

However, the RegistrationForm class extends the Struts ActionForm class which does use the Struts validator plug-in to provide validator capabilities. In the following example, the RegistrationForm Java class extends the ValidatorForm and Struts configuration XML file, struts-config.xml, instructs the application to use the Struts validator plug-in.

Sécurisé Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {
```
// private variables for registration form* 
  	private String name;
  	private String email;
  	...
  	
  	public RegistrationForm() {
  	```
  		super();
  	}
  	public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {...}
```
// getter and setter methods for private variables* 
  	...
  	}

What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.

Liste de contrôle de prévention

How to prevent CWE-106

Architecture and Design Use an input validation framework such as Struts.
Architecture and Design Use an input validation framework such as Struts.
Implementation Use the Struts Validator to validate all program input before it is processed by the application. Ensure that there are no holes in the configuration of the Struts Validator. Example uses of the validator include checking to ensure that: - Phone number fields contain only valid characters in phone numbers - Boolean values are only "T" or "F" - Free-form strings are of a reasonable length and composition
Implementation Use the Struts Validator to validate all program input before it is processed by the application. Ensure that there are no holes in the configuration of the Struts Validator. Example uses of the validator include checking to ensure that: - Phone number fields contain only valid characters in phone numbers - Boolean values are only "T" or "F" - Free-form strings are of a reasonable length and composition

Signaux de détection

How to detect CWE-106

SAST High

Exécuter une analyse statique (SAST) sur le code source à la recherche du motif non sécurisé dans le flux de données.

DAST Moderate

Exécuter des tests de sécurité applicative dynamique (DAST) contre le point de terminaison en ligne.

Runtime Moderate

Surveiller les journaux runtime pour détecter des traces d'exception inhabituelles, des entrées malformées ou des tentatives de contournement d'autorisation.

Code review Moderate

Revue de code : signaler tout nouveau code qui traite les entrées de cette surface sans utiliser les helpers du framework validés.

CWE-106

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Questions fréquentes

Frequently asked questions

Qu'est-ce que CWE-106 ?

This weakness occurs when a Java application, particularly one using the Struts framework, does not implement a structured input validation plugin like the Struts Validator. Skipping this framework forces developers to write custom validation logic, which is often error-prone and increases the risk of security flaws from improperly handled user input.

Quelle est la gravité de CWE-106 ?

MITRE n'a pas publié de note de probabilité d'exploitation pour cette faiblesse. Traitez-la comme un impact moyen jusqu'à ce que votre modèle de menace prouve le contraire.

Quels langages ou plateformes sont affectés par CWE-106 ?

MITRE lists the following affected platforms: Java.

Comment puis-je prévenir CWE-106 ?

Use an input validation framework such as Struts. Use an input validation framework such as Struts.

Comment Plexicus détecte et corrige CWE-106 ?

Le moteur SAST de Plexicus reconnaît la signature de flux de données de CWE-106 à chaque commit. Lorsqu'une correspondance est trouvée, notre agent Codex Remedium ouvre une PR de correction avec le code corrigé, les tests et un résumé d'une ligne pour le relecteur.

Où puis-je en savoir plus sur CWE-106 ?

MITRE publie la définition canonique à https://cwe.mitre.org/data/definitions/106.html. Vous pouvez également consulter la documentation OWASP et NIST pour des conseils adjacents.

Faiblesses associées

Weaknesses related to CWE-106

CWE-1173 Parent

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Struts: Plug-in Framework not in Use

What is CWE-106?

Real-world CVEs caused by CWE-106

Parcours de l'attaquant étape par étape

Vulnerable Java

Secure Java

How to prevent CWE-106

How to detect CWE-106

Don't catalog this weakness. Prove it's reachable.

Frequently asked questions

Weaknesses related to CWE-106

Improper Use of Validation Framework

Struts: Duplicate Validation Forms

Struts: Form Field Without Validator

Struts: Unvalidated Action Form

Struts: Validator Turned Off

ASP.NET Misconfiguration: Improper Model Validation

ASP.NET Misconfiguration: Not Using Input Validation Framework

Further reading

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Sample evidence handover

Server-Side Request Forgery in `webhooks/receiver`