PDF Silent HTTP Form Repurposing Attacks

This paper sheds light on the modified approach to trigger web attacks through JavaScript protocol handler in the context of browser when a PDF is opened in it. As we have seen, the kind of security mechanism implemented by Adobe in order to remove the insecurities that originate directly from the standalone PDF document in order to circumvent cross domain access. The attack is targeted on the web applications that allow PDF documents to be uploaded on the web server. Due to ingrained security mechanism in PDF Reader, it is hard to launch certain attacks. But with this technique an attacker can steal generic information from website by executing the code directly in the context of the domain where it is uploaded. The attack surface can be diversified by randomizing the attack vector. On further analysis it has been observed that it is possible to trigger phishing attacks too. Successful attacks have been conducted on number of web applications mainly to extract information based on DOM objects. The paper exposes a differential behavior of Acro JS and Brower JavaScript.

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