The Master and Parasite Attack

TL;DR

This paper introduces a new stealthy persistent parasite script attack that infects browser caches via TCP injection, enabling long-term control, propagation, and data exfiltration, with evaluations and countermeasure suggestions.

Contribution

It presents a novel persistent parasite attack method, including infection, propagation, covert communication, and exploitation techniques, with comprehensive evaluation and countermeasure recommendations.

Findings

Parasite scripts can persist long-term in browser caches.

Attackers can control parasite execution and exfiltrate data.

Effective countermeasures can mitigate parasite attack risks.

Abstract

We explore a new type of malicious script attacks: the persistent parasite attack. Persistent parasites are stealthy scripts, which persist for a long time in the browser's cache. We show to infect the caches of victims with parasite scripts via TCP injection. Once the cache is infected, we implement methodologies for propagation of the parasites to other popular domains on the victim client as well as to other caches on the network. We show how to design the parasites so that they stay long time in the victim's cache not restricted to the duration of the user's visit to the web site. We develop covert channels for communication between the attacker and the parasites, which allows the attacker to control which scripts are executed and when, and to exfiltrate private information to the attacker, such as cookies and passwords. We then demonstrate how to leverage the parasites to perform sophisticated attacks, and evaluate the attacks against a range of applications and security mechanisms on popular browsers. Finally we provide recommendations for countermeasures.