1 / 19

Mitigating Online ID Theft: Phishing and Spyware

Students : Blake Ross, Collin Jackson , Nick Miyake, Yuka Teraguchi, Robert Ladesma, Andrew Morrison Faculty : Dan Boneh and John Mitchell Special thanks to the SF-ECTF and SS . Mitigating Online ID Theft: Phishing and Spyware. Sample phishing email. http://202.69.39.30/snkee/.

asa
Download Presentation

Mitigating Online ID Theft: Phishing and Spyware

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Students: Blake Ross, Collin Jackson, Nick Miyake, Yuka Teraguchi, Robert Ladesma, Andrew Morrison Faculty: Dan Boneh and John Mitchell Special thanks to the SF-ECTF and SS. Mitigating Online ID Theft: Phishing and Spyware

  2. Sample phishing email

  3. http://202.69.39.30/snkee/.... Sample phishing site

  4. Magnitude of problem • Fastest growing crime on the Internet. • Trends: keyloggers from phishing sites. http://www.antiphishing.org

  5. What can we do about phishing? • Spam filter: • Phishing starts with email, so stop it there. • Non-trivial: phishing emails look like ordinary email. • Client-side methods: • Anti-phishing using browser plug-ins. • Anti-spyware using Virtual Machine Monitors. • Server-side methods: • Personalized web pages. • Improved user authentication (e.g. tokens or certs).

  6. PORTIA ID Protection Work • Long term effort to develop online ID protection tools. • SpoofGuard:(NDSS ’04) • Alerts user when browser is viewing a spoofed web page. • Uses variety of heuristics to identify spoof pages. • A new type of anomaly detection problem. • PwdHash: (Usenix Sec ’05) • Simple mechanism for strengthening password web auth. • SpyBlock: (under development) • A Virtual Machine (VM) approach to SpyWare defense.

  7. 1. SpoofGuard:Detect Phishing Web Sites http://crypto.stanford.edu/SpoofGuard

  8. SpoofGuard Browser Plug-in • Compute spoof index: • Weighted sum of several spoof measures • Depends on current page and browsing history • Provides two forms of information: • Passive alerts in toolbar. • Active blocking when necessary. • Challenges: • Must be easy for novice users. • Detect malicious pages yet minimize false alarms.

  9. Sample Heuristics • History Check: • Site is assumed OK if in user’s history list. • Domain Check: • Check similarity to domain in history list. • Email Check: • Suspicious if page is reached by following email link • Impact: • Ebay toolbar, Yahoo! toolbar, WholeSecure • Multiple requests for Firefox support.

  10. Current/future work • SpamAssassin extensions: • Download pages that URL’s in incoming email point to. • Run SpoofGuard heuristics on downloaded pages. • Spam archive scanning: • Automatic detection of new phishing sites. • www.spamarchive.org

  11. 2. PwdHash: Improved Pwd Mgmt http://crypto.stanford.edu/PwdHash

  12. Strengthen Web Pwd Auth • Current web auth: cleartext password over SSL • Vulnerable to phishing. • Vulnerable to break-ins at low security sites. • Simple improvement: Browser plug-in that converts a user’s pwd into a unique pwd per site: • Locate all pwd HTML elements on page: • When form is submitted replace all pwd’s by:PRFpwd(domain-name) • Phishing site only sees hash of Ebay password. • The challenge: Extremely hard to implement securelyin a modern browser!

  13. PwdHash Challenges • Javascript attacks • Pwd reset after plug-in install • Dictionary attacks (sol: EKE or SFE for equality test) • What salt to use in hash? • How to encode resulting hash? • Internet Café • Our design goal: transparent to user. • Impact: 1. Google: PhD intern. 2. TIPPI working group: MS, Mozilla, RSA

  14. Javascript attacks • Phishing site can create Javascript to steal user’s unhashed password. • Record all key-strokes sent to page • Change target-domain-name on submit • Mask regular text field as a password field

  15. Javascript attacks (cont.) • Defense 1: Password prefix / Password key • Ask user to start all passwords with “@@” • Plus-in traps all keyboard events to window. • When “@@” detected, replace subseq. keys with ‘%’ • Browser never sees pwd. • On ‘BeforeNavigate2’ event, replace ‘%%%’ in POST data with hashed pwd. • Alert user if “@@” detected in key stream while focus not on pwd field.

  16. Pwd Salting – an old idea • Hash pwd with realm provided by remote site: • HTTP 1.1 Digest Authentication • Kerberos 5 • Hash pwd with network service name: • Gabber, Gibbons, Mattias, Mayer [FC ’97]. Proxy. • Abadi, Bharat, Marais [PTO ’97] • Challenge: implementing securely in a modern browser.

  17. Spyware defense tool Current work SpyBlock

  18. https page https junkdata Junk Keys PwdKey SpyBlock design • Proxy VM keeps sensitive user info away from SpyWare. • User hits pwdkey before and after typing sensitive info. Proxy VM Firefox SpyWare apps Guest OS VMWare ACE Server / Xen

  19. Summary • Long term effort focused on ID protection tools. • Current tools: SpoofGuard, PwdHash, Current/future work: SpyBlock • Strong focus on technology transfer: • Interns help do tech transfer. • Source code available on PORTIA web site. • Close collaboration with SF-ECTF.

More Related