Who changed my browser settings? Silently modifying the Secure Preferences of Chrome
Typ
Examensarbete för masterexamen
Program
Publicerad
2019
Författare
Axelsson, Gustav
Sundling, Joakim
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Google Chrome is as of today the most used web browser in the world. With millions
of daily users the security of the browser is of high importance. When using Google
Chrome each user obtains a couple of configuration files for storing information such
as bookmarks, browser history, homepage and a multitude of other settings. One of
these files is the Secure Preferences file in which some of the browsers most sensitive
settings are stored. In order to protect these settings Chrome has added custom
Hash-based Message Authentication Codes (HMACs) that are used to ensure that
no settings are silently modified by third parties. This thesis describes how this
security can be circumvented and implements a versatile script, for Windows, that
is able to alter all the information stored in Secure Preferences without alerting
the browser. This thesis also describes the steps taken in order to reproduce the
hashing mechanism of Chrome as well as how different preferences can be exploited.
An extension is developed which makes it possible to run the script from the Chrome
browser. The script is then evaluated together with the extension by both checking
the correctness of the HMAC calculation and how well it is able to perform a variety
of exploits. This thesis proves that it is indeed possible to break the security of the
Secure Preference file. By reproducing and replacing the HMACs which gives the
user of the script the possibility to alter frequently used functions in Chrome such
as homepage, new tabs, extensions and default search engine.
Beskrivning
Ämne/nyckelord
Computer , science , computer science , engineering , project , thesis , Google Chrome , preferences , secure preferences