Using setters in Struts 2 ActionSupport is security-sensitive. For example, their use has led in the past to the following vulnerabilities:

* http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-1006[CVE-2012-1006]

All classes extending ``++com.opensymphony.xwork2.ActionSupport++`` are potentially remotely reachable. An action class extending ActionSupport will receive all HTTP parameters sent and these parameters will be automatically mapped to the setters of the Struts 2 action class. One should review the use of the fields set by the setters, to be sure they are used safely. By default, they should be considered as untrusted inputs.


== Ask Yourself Whether

* the setter is needed. There is no need for it if the attribute's goal is not to map queries' parameter.
* the value provided to the setter is properly sanitized before being used or stored. (*)

(*) You are at risk if you answered yes to this question.


== Recommended Secure Coding Practices

As said in Struts documentation: https://struts.apache.org/security/#do-not-define-setters-when-not-needed["Do not define setters when not needed"]

Sanitize the user input. This can be for example done by implementing the ``++validate()++`` method of ``++com.opensymphony.xwork2.ActionSupport++``.


== Sensitive Code Example

[source,java]
----
public class AccountBalanceAction extends ActionSupport {
  private static final long serialVersionUID = 1L;
  private Integer accountId;

  // this setter might be called with user input
  public void setAccountId(Integer accountId) {
    this.accountId = accountId;
  }

  @Override
  public String execute() throws Exception {
    // call a service to get the account's details and its balance
    [...]
    return SUCCESS;
  }
}
----


== See

* OWASP - https://owasp.org/www-project-top-ten/2017/A1_2017-Injection[Top 10 2017 Category A1 - Injection]


ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Make sure that executing this ActionSupport is safe.


=== Highlighting

First: the ``++execute++`` method

Second: locations where the setters are defined.


'''
== Comments And Links
(visible only on this page)

=== is related to: S4529

=== on 26 Mar 2018, 20:52:10 Alexandre Gigleux wrote:
Struts 2 Examples: \https://github.com/apache/struts-examples


This rule should raise an issue if:

* the class is extending ``++com.opensymphony.xwork2.ActionSupport++``
* the class overrides the ``++execute++`` method
* the class is having at least one setter method

=== on 26 Mar 2018, 20:56:59 Alexandre Gigleux wrote:
This is a "Security Hotspot".

=== on 27 May 2020, 16:47:21 Eric Therond wrote:
Deprecated because it overlaps with SonarSecurity

endif::env-github,rspecator-view[]