Vulnerability Note VU#442845

XML-RPC is a specification and a set of implementations that allow software running on disparate operating systems and in different environments to make procedure calls over the Internet. XML-RPC uses HTTP for the transport protocol and XML for the data encoding. Several independent implementations of XML-RPC exist for PHP applications.

A common flaw in the way that several XML-RPC PHP implementations pass unsanitized user input to eval() within the XML-RPC server results in a vulnerability that could allow a remote attacker to execute code on a vulnerable system. An attacker with the ability to upload a crafted XML file could insert PHP code that would then be executed by the web application using the vulnerable XML-RPC code.

Remote attackers may be able to execute PHP code of their choosing on a vulnerable system. The code would be executed in the context of the server program that runs the corresponding web application. Secondary impacts of a compromised web service account include, but are not limited to, malicious modification of web site data, information disclosure, and access that may be leveraged to gain additional system privileges.

Upgrade or apply a patch

Various vendors have published patches and updated versions of their software to address this issue. Please see the Systems Affected section of this document for information on a specific product or vendor.

Note that because the vulnerability exists in a common extension module, any application that uses the flawed code, including custom applications, may expose the vulnerability. Developers that bundle their own versions of the XML-RPC library with their application should exercise extra care to evaluate their own potential use of the vulnerable code.