CVE-2015-9251

Steps to Reproduce

Google’s security team reported this Medium-level security vulnerability. The vulnerability allows 3rd party arguments to $.get() to auto-execute if the content type is text/javascript.

In practical terms, applications that use $.get() are vulnerable if they query an untrusted/compromised website.

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Addressing the Issue

 Successful exploitation of this vulnerability may allow attackers to obtain sensitive information, steal cookies and/or execute Javascript or HTML code. Clients using jQuery prior to 3.0.0 should upgrade immediately to this version (the fix was never applied to the 2.x branch).

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Learning and Prevention

One way cross-site Scripting (XSS) vulnerabilities are expressed is by visiting compromised websites. In this case, the $.get() command is used to visit a site that has code intended to gain access to data or protected subsystems. The browser unknowingly executes the malicious code.

Although it’s important when using $.get() to ensure that the target site is a known, safe entity, this is not always possible. Thus, escaping the content obtained from the target site is the customary method to guard against this exploit (“escaping” is a form of data sanitization). The process of escaping the content converts the code into something that can’t be executed, thereby rendering the payload safe.

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Conclusion

Obtain the latest version of jQuery with the fix applied by being a customer of the HeroDevs jQuery NES service. Customers get immediate notification and are able to easily update their systems. Contact HeroDevs to get Never-Ending support for jQuery today.

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Resources

‍NIST CVE-2015-9251 entry