Phishing markus.jakobsson@parc.com. Conventional Aspects of Security Computational assumptions...

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Phishing

markus.jakobsson@parc.com

Conventional Aspects of Security• Computational assumptions

– E.g., existence of a one-way function, RSA assumption, Decision Diffie-Hellman

• Adversarial model– E.g., access to data/hardware, ability to corrupt,

communication assumptions, goals

• Verification methods– Cryptographic reductions to assumptions, BAN logic

• Implementation aspects– E.g., will the communication protocol leak information that

is considered secret in the application layer?

The human factor of security

Configuration

NeglectDeceit

The human factor: configuration

Weak passwordsWith Tsow, Yang, Wetzel: “Warkitting: the Drive-by Subversion of Wireless Home Routers”

(Journal of Digital Forensic Practice, Volume 1,

Special Issue 3, November 2006)

Wireless

firmware update

Shows that more than 50% of APs are vulnerable

wardrivingrootkitting

The human factor: configuration Weak passwords

With Stamm, Ramzan: “Drive-By Pharming”

(Symantec press release, Feb 15, 2007; top story on Google Tech news on Feb 17; Cisco warns their 77 APs are vulnerable, Feb 21; we think all APs but Apple’s are at risk. Firmware update tested on only a few. Paper in submission)

Wireless nvram

value setting

“Use DNS server x.x.x.x”

And worse: geographic spread!

The human factor: neglect

The human factor: deceit

(Threaten/disguise - image credit to Ben Edelman)

The human factor: deceit

Self: “Modeling and Preventing Phishing Attacks” (Panel, Financial Crypto, 2005 - notion of spear phishing)With Jagatic, Johnson, Menczer: “Social Phishing” (Communications of the ACM, Oct 2007)With Finn, Johnson: “Why and How to Perform Fraud Experiments” (IEEE Security and Privacy,March/April 2008)

Experiment Design

Gender Effects

To Male

To Female

To Any

FromMale

FromFemale

FromAny

0%

10%

20%

30%

40%

50%

60%

70%

80%

Success Rate

From Male 53% 78% 68%

From Female 68% 76% 73%

From Any 65% 77% 72%

To Male To Female To Any

B

eBay

A

Ethical and accurate assessmentsWith Ratkiewicz “Designing Ethical Phishing Experiments:

A study of (ROT13) rOnl auction query features” (WWW, 2006)

Reality:

3 credentials

1 2

4

BA

Ethical and accurate assessmentsWith Ratkiewicz “Designing Ethical Phishing Experiments:

A study of (ROT13) rOnl auction query features” (WWW, 2006)

Attack:

1 (spoof)

2 credentials

BA

Ethical and accurate assessmentsWith Ratkiewicz “Designing Ethical Phishing Experiments:

A study of (ROT13) rOnl auction query features” (WWW, 2006)

Experiment: 3 (spoof)

A

1

2

eBay

4 credentialsYield (incl spam filtering loss): 11% + 3% …“eBay greeting” removed: same-

1

2

5

Mutual authentication

in the “real world”

With Tsow,Shah,Blevis,Lim,“What Instills Trust? A Qualitative Study of Phishing” (Abstract at Usable Security, 2007)

starting with 4901

How does the typical Internet user identify phishing?

Spear Phishing and Data Mining Current attack style:

Approx 3% of adult Americans report to have been victimized.

Spear Phishing and Data Mining More sophisticated attack style:

“context aware attack”

How can information be derived?

Jane Smith Jose Garcia

… and little Jimmy Garcia

Jane Garcia, Jose Garcia

Let’s start from the end!

“Little” Jimmy

his parentstheir marriage license

and Jimmy’s mother’s maiden name: Smith

More reading: Griffith and Jakobsson, "Messin' with Texas:Deriving Mother's Maiden Names Using Public Records."

www.browser-recon.info

Approximate price list:

PayPal user id + password $1

+ challenge questions $15

Why?

Password Reset:Typical Questions

• Make of your first car• Mother’s maiden name • City of your birth • Date of birth • High school you graduated from• First name of your / your sister’s best friend• Name of your pet• How much wood would a woodchuck …

Problem 1: Data Mining

• Make of your first car?– Until 1998, Ford has >25% market share

• First name of your best friend?– 10% of males named James (Jim), John, or

Robert (Bob or Rob) + Facebook does not help

• Name of your first / favorite pet?– Top pet names are online

Problem 2: People Forget

• Name of the street you grew up on?– There may have been more than one

• First name of your best friend / sisters best friend?– Friends change, what if you have no sister?

• City in which you were born?– NYC? New York? New York City? Manhattan? The

Big Apple?

• People lie to increase security … then forget!

Intuition

Preference-based authentication:• preferences are more stable than long-

term memory (confirmed by psychology research)

• preferences are rarely documented (in contrast to city of birth, brand of first car, etc.) … especially dislikes!

Our Approach (1)

Demo at Blue-Moon-Authentication.com, info at I-forgot-my-password.com

Our Approach (2)

And next?

http://www. democratic-party.us/LiveEarth

http://www. democratic-party.us/LiveEarth

Countermeasures?

• Technical – Better filters– CardSpace– OpenId

• Educational– SecurityCartoon– Suitable user interfaces

• Legal

Interesting?

Internships at PARC / meet over coffee / etc.

markus.jakobsson@parc.com

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