TwoKind authentication: protecting private information in untrustworthy environments

ABSTRACT

Users often log in to Internet sites from insecure computers and more recently have started divulging their email passwords to social-networking sites, thereby putting their private communications at risk. We propose and evaluate TwoKind Authentication, a simple and effective technique for limiting access to private information in untrustworthy environments. In its simplest form, TwoKind offers two modes of authentication by providing a low and a high authenticator. By using a low authenticator, users can signal to the server that they are in an untrusted environment, following which the server restricts the user's actions.

We seek to evaluate the effectiveness of multiple authenticators in promoting safer behavior in users. We demonstrate the effectiveness of this approach through a user experiment - we find that users make a distinction between the two authenticators and generally behave in a security-conscious way, protecting their high authenticator the ma jority of the time. Our study suggests that TwoKind will be beneficial to several Internet applications, particularly if the privileges associated with the low authenticator can be customized to a user's security preferences.

REFERENCES

• 1: K. Bailey, A. Kapadia, L. Vongsathorn, and S. W. Smith. TwoKind authentication: Protecting private information in untrustworthy environments (extended version). Technical Report TR2008--632, Dartmouth College, Aug 2008.
• 2: Katelin Bailey , Linden Vongsathorn , Apu Kapadia , Chris Masone , Sean W. Smith, TwoKind authentication: usable authenticators for untrustworthy environments, Proceedings of the 3rd symposium on Usable privacy and security, July 18-20, 2007, Pittsburgh, Pennsylvania [doi>10.1145/1280680.1280712]
• 3: Jim Basney , Marty Humphrey , Von Welch, The MyProxy online credential repository: Research Articles, Software—Practice & Experience, v.35 n.9, p.801-816, July 2005 [doi>10.1002/spe.v35:9]
• 4: Ernie Brickell , Jan Camenisch , Liqun Chen, Direct anonymous attestation, Proceedings of the 11th ACM conference on Computer and communications security, October 25-29, 2004, Washington DC, USA [doi>10.1145/1030083.1030103]
• 5: eTrade Trading Passwords. https://www.etradeaustralia.com.au/EStation/hep aec connecting.asp.
• 6: Scott Garriss , Ramón Cáceres , Stefan Berger , Reiner Sailer , Leendert van Doorn , Xiaolan Zhang, Towards Trustworthy Kiosk Computing, Proceedings of the Eighth IEEE Workshop on Mobile Computing Systems and Applications, p.41-45, March 08-09, 2007 [doi>10.1109/HOTMOBILE.2007.19]
• 7: Shirley Gaw , Edward W. Felten, Password management strategies for online accounts, Proceedings of the second symposium on Usable privacy and security, July 12-14, 2006, Pittsburgh, Pennsylvania [doi>10.1145/1143120.1143127]
• 8: Leslie Lamport, Password authentication with insecure communication, Communications of the ACM, v.24 n.11, p.770-772, Nov. 1981 [doi>10.1145/358790.358797]
• 9: J. Marchesini and S. W. Smith. SHEMP: Secure Hardware Enhanced MyProxy. In PST, 2005.
• 10: J. Marchesini, S. W. Smith, and M. Zhao. Keyjacking: the surprising insecurity of client-side SSL. Computers and Security, 24(2):109--123, 2005.
• 11: RSA SecurID. http://www.rsa.com/node.aspx?id=1156.
• 12: J. H. Saltzer and M. D. Schroeder. The protection of information in computer systems. Communications of the ACM, 17(7), July 1974.
• 13: A. Seshadri, A. Perrig, L. van Doorn, and P. Khosla. SWAtt: Software-based attestation for embedded devices. In Proceedings of the IEEE Symposium on Security and Privacy, May 2004.
• 14: Sara Sinclair , Sean W. Smith, PorKI: Making User PKI Safe on Machines of Heterogeneous Trustworthiness, Proceedings of the 21st Annual Computer Security Applications Conference, p.419-430, December 05-09, 2005 [doi>10.1109/CSAC.2005.43]
• 15: Jeff Yan , Alan Blackwell , Ross Anderson , Alasdair Grant, Password Memorability and Security: Empirical Results, IEEE Security and Privacy, v.2 n.5, p.25-31, September 2004 [doi>10.1109/MSP.2004.81]

INDEX TERMS

Primary Classification:
  K. Computing Milieux
  K.6 MANAGEMENT OF COMPUTING AND INFORMATION SYSTEMS
      K.6.5 Security and Protection (D.4.6, K.4.2)
          Subjects: Authentication

Additional Classification:
  H. Information Systems
  H.1 MODELS AND PRINCIPLES
      H.1.2 User/Machine Systems
          Subjects: Human factors

General Terms:
Human Factors, Security

Keywords:
authenticators, passwords, principle of least privilege