Executing code dynamically is security-sensitive. It has led in the past to the following vulnerabilities:

* http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-9807[CVE-2017-9807]
* http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-9802[CVE-2017-9802]

Some APIs enable the execution of dynamic code by providing it as strings at runtime. These APIs might be useful in some very specific meta-programming use-cases. However most of the time their use is frowned upon as they also increase the risk of https://owasp.org/www-community/attacks/Code_Injection[Injected Code]. Such attacks can either run on the server or in the client (exemple: XSS attack) and have a huge impact on an application's security.


This rule raises issues on calls to ``++eval++`` and ``++Function++`` constructor. This rule does not detect code injections. It only highlights the use of APIs which should be used sparingly and very carefully. The goal is to guide security code reviews.

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== Sensitive Code Example

----
let value = eval('obj.' + propName); // Sensitive
let func = Function('obj' + propName); // Sensitive
----

== Exceptions

This rule will not raise an issue when the argument of the ``++eval++`` or ``++Function++`` is a literal string as it is reasonably safe.

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== Implementation Specification
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== Comments And Links
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