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A F ew Miscellaneous Topics on Security. Sankar Roy. Acknowledgement. In preparing the presentation slides and the demo, I received help from Professor Simon Ou Professor Gurdip Singh Professor Eugene Vasserman. Agenda. Password cracking Information gathering (reconnaissance)
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A Few Miscellaneous Topics on Security Sankar Roy
Acknowledgement In preparing the presentation slides and the demo, I received help from • Professor Simon Ou • Professor Gurdip Singh • Professor Eugene Vasserman
Agenda • Password cracking • Information gathering (reconnaissance) • Spoofed emails or phone calls • Threats through emails • phishing attack • other attacks • Risks of swiping a credit card in an untrusted place • Security concerns associated with RFID tags
Password-based Security • We use passwords everywhere • email accounts, bank accounts, social networking sites, personal computers, and so on… • What makes a good password • long but should be easy for you to remember • should be very difficult for the attacker to guess
Good or Bad Passwords? 7@Ack ilove soccer 07deserteagle chuck#0123 5lakers5 oliveoil7 john1 eagle1900 beethoven5th PTL!1g1M05 Pizza qwerty123 dhx@yahoo.comjustin_bieber_sux! h.o.u.s.e {T@!4u2N9^}& $trongPassword WeRtheChamp10n !ILh2dW&%D@etF1 zeppelinIV
Password Cracking • How long is good enough? • we can compute the password strength • use alphanumeric letters, big case, and small case • use special characters • Dictionary attack • the attacker first tries a list of frequently used passwords • then, she may try all possible combinations (brute-force) • Social engineeringto aid in cracking • information gathering can work if, as an example, a family member or pet’s name is used as the password • you may leak your secret while responding to a fake email or phone call
Password Crackers Tools • Hydra, Medusa • can crack network logon passwords (e.g. FTP, HTTP, VNC, POP3) • Ophcrack • Pre-computed Rainbow tables can reduce cracking time • Top 10 Password Crackers: • http://sectools.org/crackers.html
Information Gathering The attacker can employ several techniques • Uses Internet search engines and social networks • collect names, address, login names, email addresses, host machine’s names, etc. • automated tools available, e.g. theHarvester • Sends information requests via fake email or phone • and waits for response from a potential victim • Does dumpster diving • Buys information from the black market
TheHarvester: An Automated Miner • Atool for gathering e-mail accounts, user names and hostnames from different public sources. • It supports multiple sources: • Google, Bing, LinkedIn, etc. • Caution: the attacker can use all sources • An example: • Using this tool a SPAMer can collect your email address (e.g. from your public webpage) • Anti-Harvesting methods • Address munging (e.g. instead of alice@abc.com publish “aliceat abc dot com") • Using images to display part or all of an email address
Spoofed Email • Email system does NOT provide “sender authentication” • in a spoofed email, the sender’s address is altered • receiving an email proves nothing about the actual sender • Spoofed email sending software is available • which is used in sending SPAM or phishing email
Let’s do a Hands-on Activity • Note: there are some websites via which anybody can send a spoofed email to anybody • Let’s test one of them to understand how easy it is for the attacker to send a fake message • Caution: this activity is only for the testing purpose. It is a crime to send a phishing email.
Gmail Ways to Detect Email Spoofing • Sender Policy Framework (SPF) is an email validation system • allows administrators of a domain D to specify which hosts are allowed to send email from D • checks authorization of the sender’s IP addresses using the DNS system • DomainKeys Identified Mail (DKIM)is a way to digitally sign emails • verifies if the email was actually sent by a particular domain D as claimed in the email.
How to Check the Authentication Information of a Message on Gmail Acknowledgement: Gmail’s User Guide
Phone Caller Id Spoofing • Makes a phone call appear to have come from any number the caller wishes • Most common spoofing method is through the VoIP system • Open source tools e.g. Asterisk, FreeSWITCHcan be used for spoofing
Email Threats • Security risks include • phishing scams • links (in body) or attachments have malware • Nowadays these risks are high • bad guys can hire a SPAM sending botnet to launch a large-scale attack • millions of valid email addresses are available for sale in the underground black market
Phishing Attack: An Example Email Subject: E-mail Security Alert!From: Kansas State University <notifications@ksu.edu>Date: Tue, 18 Dec 2012 06:14:01 +0900 (JST) Access to your e-mail account is about to expired.Please Click here <http://sevenes.com/zboard/ksu/> to restore access to your e-mail account.We apologise for any inconvenience and appreciate your understanding. Regards, Kansas State University Acknowledgement: K-State IT Security Threats Blog
Phishing Attack: Another Example Acknowledgement: FraudWatchInternational.com
More on the Phishing Attack • Fake email messages apparently coming from a trusted person or institution(e.g. a bank) • trickpeople into passing secret information such as passwords, credit card numbers and bank account numbers. • A phishing email can have links to • fake login pages impersonating financial institutions • malware, virus, spyware, etc.
Countering Phishing Attack • Remember that the institution (e.g. your bank or KSU) will never ask for your secret through emails • Be suspicious when you receive an email; know that the email sender address can be spoofed • Avoid clicking any link in such emails • double check if the link URL name is fishy • visit only https links; do not proceed if you get a bogus certificate warning • Do not respond to any such email; call them if unsure • Always use the latest versions of web browsers
How to Recognize a Fraudulent Email? • Train yourself by studying several resources which are available on the KSU ITS website • Some resource examples are • Anti-Phishing Working Group www.antiphishing.org (http://www.antiphishing.org/resources/Educate-Your-Customers/) • Looks Too Good To Be True www.lookstoogoodtobetrue.com
Examples of Phishing Scams • Advance fee scam • Job offer scam • Nigerian scam • Beneficiary of a will scam • Over-paying (Craigslist) scam • Charitable donation scam • Facebook friend scam Acknowledgement: K-State ITS
Spear Phishing • A more targeted method of phishing • only known members of the targeted institution receive the email • Email addresses are acquired by • joining a mailing list • buying a list from a hacker • guessing email addresses based on the general format e.g. abc123@k-state.edu
Threats via Email Attachment • Email attachment may contain malware • worms, virus, Trojan horses, etc. • which can seriously damage your computer • Do not open any suspicious attachment • it can trigger/execute the malware • just delete such emails • Install an anti-virus software on your computer • ensure that it scans all attachments automatically before you open them • Anti-virus “Trend Micro Security” is available to K-staters
Risks of Swiping a Credit Card in an Untrusted Place • An ATM skimmer can steal the card secret • later the bad guys collect the data from the skimmer device • difficult to detect: it blends in with the cash machine in form and color • Typically two components build a skimmer • a device that fits over the card acceptance slot and steals the data stored on the card’s magnetic stripe • a pinhole camera built into a false panel that thieves can fit above or beside the PIN pad. • Risk Mitigation • try to avoid using ATMs in unknown non-standard places • frequently check your credit card transactions and report fraud, if any
Basics of RFID Technology • The tracking system has three components: • ascanning antenna • a RFID tag programmed with information • a transceiver to interpret the data • A RFID tag can be read • from a distant place (up to 300 feet) • no need to be in the line of sight (unlike a barcode) • RFID tags have NO batteries • so, it remains usable for long time
RFIDTags: Security and Privacy Concerns • A thief with a scanner can activate the RFID tag and read its contents • example: if someone walks by your bag of books with a "sniffer”, that person can get a complete list of books. • Concern with RFID devices in a company badge • example: a RF field may make the RFID chip in the badge spill the badge secret, allowing the thief access.
Summary • We discussed a few common security issues. • We presented the standard countermeasures to mitigate the risks • This was the last class of CIS 490 • Thanks a lot for your time and cooperation