PHAD- A Phishing Avoidance and Detection Tool Using Invisible Digital Watermarking

1
PHAD- A Phishing Avoidance and Detection Tool
Using Invisible Digital Watermarking
By Sonali Batra
Web 2.0 Security and Privacy 2014
2
What is Phishing Phishing Trends

• A form of social engineering
• Phishers send fake site's url in spam mail
• A huge problem!
• Number of unique phishing sites in Sept 2013
  alone 45,115 ( 56.22 contain some form of
  target name in url)
• Number of unique phishing email reports received
  by APWG - 56,767

Web 2.0 Security and Privacy 2014
3
PHAD A Phishing Avoidance and Detection Tool

• Downloadable extension to Firefox browser.
• Uses invisible digital watermarking.
• Uses uniqueness of domain name of website.
• Uses robust digital watermarking.
• Implemented using Outguess a universal
  steganographic tool.
• Based on observation that some phishers copy
  content of legitimate sites like source code and
  images to use in fake site.

Web 2.0 Security and Privacy 2014
4
Working of PHAD

• Companies invisibly watermark their logo images
  with the domain names of their websites.
• When phisher copies the image, the watermark
  travels along with it.
• Browser on client side detects watermark and
  compares to domain name.
• If both match, website is legitimate else website
  is phished.

Web 2.0 Security and Privacy 2014
5
Related Work

• Huajun Huang, Yaojun wang, Lili Xie and Liqing
  Jiang.An Active Anti-phishing Solution Based on
  Semi- fragile Watermark.
• Watermark concatenation of domain name and other
  parameters into source code of website by equal
  tag method.
• Can easily be reversed if phisher is aware of
  scheme.

Web 2.0 Security and Privacy 2014
6
Disclaimer

• PHAD is intended to serve only as a first defense
  and not as a complete filter.
• Artistic hackers having plenty of time on their
  hands could make a similar looking logo.
• If a phisher has access to the client watermark
  detection software, a phisher could observe it to
  remove watermark. Then re-watermark image.
• No known software exists to automate this yet.
• PHAD significantly increases effort required by
  phisher.

Web 2.0 Security and Privacy 2014
7
A Few Questions

• What if phisher takes screenshot or photograph of
  image? - watermark shall persist across
  screenshots and good quality photographs
• What if a company has multiple domain names? Eg
  google.in and google.us We shall watermark all
  the domain names into the image. The client
  checks if at least one matches the extracted
  watermark.
• What if a company has multiple logos? - All
  domain names watermarked in all logos.

Web 2.0 Security and Privacy 2014
8
A Few Questions

• What if a website wants to embed logo of another
  company in its webpage? eg. CNN runs a story on
  Google or Facebook.
• Multiple images allowed on page.
• Company having highest ratio of images compared
  to domain name.

Web 2.0 Security and Privacy 2014
9
A Few Questions

• What if a website has two or more watermarked
  images? - The company having the highest ratio
  shall be compared to domain name.
• Instead, if both of images were to be compared,
  PHAD would fail. This is because attacker could
  put original image with watermark of company and
  her own image with her own fake site's watermark
  (which would match domain name of fake site)

Web 2.0 Security and Privacy 2014
10
A Few Questions

• How is this better than using Https?
• Users are not aware that url should be preceded
  by https instead of http.
• No single point of failure.
• Https can be used as added security measure along
  with PHAD.

Web 2.0 Security and Privacy 2014
11
Future Work

• Implement scheme for other browsers and other
  operating systems instead just firefox and
  linux.
• Audit top 20 banks and top 100 websites to see if
  they would be able to use this approach or not.
• Conduct a 'Wizard of Oz' study to demonstrate
  that users like and understand the approach.

Web 2.0 Security and Privacy 2014
12
Questions???
Web 2.0 Security and Privacy 2014