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Security in Cloud Computing Thanks to Research talk at UA | Ragib Hasan | www.ragibhasan.com | UAB CIS 12/02/11 Calvin Vreeland Security • How do you know data in cloud is safe and secure? • Even reputable providers can be hacked What the “experts” are saying? [Cloud Computing] is a security nightmare and it can't be handled in John Chambers traditional ways. CISCO CEO It’s stupidity. It’s worse than stupidity Richard Stallman GNU 3 Businesses don’t trust clouds (yet) Almost 75% of business CFOs are still afraid to use clouds for sensitive data due to lack of security 4 Traditional systems security vs Cloud Computing Security Securing a traditional Securing a cloud system 5 Traditional systems security vs Cloud Computing Security Analogy Securing a house Securing a motel Owner and user are Owner and users are almost often the same entity invariably distinct entities 6 Traditional systems security vs Cloud Computing Security Securing a house Securing a motel Biggest user concerns Biggest user concern Securing perimeter Securing room against Checking for intruders (the bad guy in next Securing assets room | hotel owner) 7 Cloud security involves securing across multiple dimensions of the cloud Data and computation integrity and confidentiality Infrastructure, Data Privacy topology Networking Forensics 8 Research on Cloud Computing Security: A High Level View • Novel attacks • Trustworthy cloud architectures • Data integrity and availability • Computation integrity • Data and computation privacy • Data forensics • Misbehavior detection • Malicious use of clouds • Economic attacks 9 Co-tenancy in clouds creates new attack vectors A cloud is shared by multiple users Malicious users can now legally be in the same infrastructure Misusing co-tenancy, attackers can launch side channel attacks on victims any attack based on information gained from the physical implementation of a cryptosystem, rather than brute force or theoretical weaknesses in the algorithms. E.g., timing information, power consumption, electromagnetic leaks or even sound can provide an extra source of information which can be exploited to break the system Example: the Topology attack on Amazon EC2 (“Hey You! Get off of my Cloud …” CCS 2009) 10 Today’s cloud architectures act like big black boxes Clients have no idea of or control over what is happening inside the cloud Clients are forced to trust cloud providers completely Existing Approaches: TCCP (uses TPM), CloudProof The Trusted Platform Module (TPM) installed on certain motherboards is an extra chip that is designed to aid in the generation of certain types of cryptographic keys to use in various parts of the computer. 11 Today’s clouds provide no guarantee about outsourced data Problem: Dishonest cloud providers can throw data away or lose data. Malicious intruders can delete or tamper with data. Clients need reassurance that the outsourced data is available, has not been tampered with, and remains confidential. Example Approaches: Provable Data Possession (PDP), Proof of Retrievability (PoR), HAIL 12 Ensuring confidentiality of data in outsourced computation is difficult Most type of computations require decrypting data before any computations If the cloud provider is not trusted, this may result in breach of confidentiality Existing Approaches: Homomorphic encryption, TCCP 13 Privacy is often the victim when using a cloud … It is almost impossible to provide privacy of sensitive personal information in computation outsourcing Using Google spreadsheets to maintain SSN Popular distributed computation systems such as MapReduce are NOT designed with privacy in mind 14 Clients have no way of verifying computations outsourced to a Cloud Scenario User sends her data processing job to the cloud. Clouds provide dataflow operation as a service (e.g., MapReduce, Hadoop etc.) Problem: Users have no way of evaluating the correctness of results Existing Approaches: Runtime Attestation, Majority voting, Redundant operations 15 Assessing the Capability of a Cloud Provider is difficult due to the black box model Availability, fault-tolerance, and resilience are important to clients for mission-critical data But cloud providers do not want to reveal their capability or redundancy So, clients need a way to remotely verify the capability claims 16 Data Forensics in Clouds is difficult Certain Government regulations mandate the ability to audit and run forensic analysis on critical business or healthcare data Clouds complicate forensic analysis, since the same storage infrastructure is shared by many clients Cloud providers are not willing to open up their entire storage for forensic investigations. 17 Clouds can be used for malicious purposes Adversaries can rent clouds temporarily to create a large scale botnet very quickly Clouds can be used for spamming, Denial of service, brute force password breaking, and other attacks Example: WPACracker.com – Claims to break WPA passwords for $17 in under 20 minutes, using a cloud 18 Economy matters! Sometimes, economic targets are more effective than technical targets Attacks can target economic viability of cloud users (by consuming extra resources), or of cloud providers (by fraudulently consuming cloud resources) 19 Hassan strategy Question: How can we make clouds more accountable? Approach: By maintaining secure and verifiable provenance chains for all data and computations outsourced to a cloud, clients can get more accountability. Provenance of data Provenance of computations What happened to the data object How was a particular result while it was inside the cloud? (i.e., computed inside a cloud? entire history of the data object) Challenges: How to ensure correct collection of provenance inside a cloud, even when the cloud provider may not be trustworthy? Owner, source History of ownership of a valued object (Largely) Unexplored Areas Legal/policy issues and regulatory compliance: How does cloud computing fit in with data security laws and regulations such as SOX, HIPAA? Sarbanes Oxley – result of Enron, accuracy of financial reporting data For example, If I store my data in Amazon, can the Govt. subpoena Amazon to access my data without violating 4th amendment? unreasonable search and seizure Will a cloud based storage system comply with SOX? 21 Issues related to users of the cloud • Sensitive Information – SLA may allow access and catalog and use info in ways never intended • Share data with marketing firm – Google’s policy – company will share data with gov if “good faith belief” access is necessary to fulfill lawful requests – Government can more easily subpoena 3rd party than privately owned – Closed Subpoena – provider legally prohibited from telling customers data has been given to the government – Google’s problem or SLA may say not responsible Today’s clouds provide no guarantee about outsourced data Amazon’s Terms of services 23 The government – yes it can be good – Governmental regulations: • If doing business for EU, cannot store in US • If credit card data, restrictions on where can store data, cannot allow free block to be included in another customer’s block of storage Examples of problems • AOL releated 650k customer search terms on public web page • MS released search data to US DOD in child porn case • British gov misplaced 25 M taxpayer records • Retailers lose credit card numbers Anecdotes “A short account of an interesting or amusing nature” Why? Locked Out Nick Saber isn’t happy now. Monday afternoon, after lunch, Nick came back from lunch to find out that he couldn’t get into his Gmail account. Further, he couldn’t get into anything that Google made (beside search) where his account credentials once worked. When attempting to log in, Nick got a single line message: Sorry, your account has been disabled. [?] That’s it. No, Google, that’s not it. Somewhere, deep inside the bowels of Google-land, something went wrong and an innocent person suffers the loss of his data. This is serious failure! One point the story highlights is a hard lesson for users: Don’t trust the cloud at this early stage in its evolution. http://blogs.zdnet.com/projectfailures/?p=958 Cloud Goes Dark Amazon.com Web Service's hosted storage service went down Friday morning, frustrating many Web site customers and refreshing concerns with the ballyhooed approach of cloud computing. An online forum spiked with customer complaints Friday morning as some people found that content stored on Amazon's Simple Storage Service (S3) was unavailable or performed slowly. The service was restored a few hours later, according to an Amazon technician. The first forum posting was timed at 5 a.m. PT, and the service was back up at just past 9 a.m. The glitch sent a ripple through the blogosphere as Web entrepreneurs, who are increasingly using Amazon's hosted computing services, pondered whether they needed a back-up plan or a more traditional hosting provider. On the forum, some people complained about how the service glitch essentially put them out of business temporarily. http://news.cnet.com/8301-17939_109-9873068-2.html Google Docs Down Google's Documents and Spreadsheets service went down for approximately 45 minutes earlier this morning. The service, Google's online productivity suite, went from having some features not working, like the log-out button and the document creation drop- down menu, to coming up with a 404 page. The downtime calls into question the importance that online Web applications play in business use, as well as how Google's free document services have come to replace software solutions such as Microsoft Office for some users or teams that use Google's real-time collaboration features. http://news.cnet.com/8301-17939_109-9985608-2.html Digital Railroad "Everyone is downloading now and their FTP has slowed to a crawl," one Digital Railroad member told News Photographer magazine earlier this afternoon, before the site went dark. It's estimated that there may have been as many as 1,900 client archives on Digital Railroad's servers as of today. http://www.nppa.org/news_and_events/news/2008/10/digitalrailroad.html Security Benefits in the Cloud • Centralized data – can make it more secure • Reduced data loss (12K laptops lost in US airports) – How secure are laptops? • If limit employee downloads, can limit data loss • Easier to monitor security if only one location • Can move data to another machine • Logging is better in the cloud (C2 audit trail) – High overhead, but the cloud can handle it Security Benefits in the Cloud • Security bundled in, no need to buy 3rd party security SW • Can perform patches and upgrades offline, test off-line versions of production environment • Vendors more likely to develop more efficient security SW • SaaS/PaaS providers do security testing (lower cost for security testing split amongst all users) Regulatory Issues • No existing regulation • Despite its size, Google could still fail (look at GM or those banks that were too big to fail…) • Government backed insurance? • Should government regulate the cloud? – Safe guard for loss or theft? • Who owns the data? – Law enforcement easier access to cloud than PC? Regulatory Issues • Do people really understand privacy and security implications of email, Facebook, etc? • US courts ruled private data in cloud does not have same level of protection from law enforcement searches • 49% concerned if cloud shared files with law • 80% concerned if used photos for marketing • 68% concerned is used personal information for personalized ads • 63% concerned if provider kept data after used deleted Regulatory Issues • Should government agencies store data on clouds? • Procurement regulations will have to change • GSA pushing for cloud to reduce energy • US gov. spends $480 M on electricity for computers Security in Clouds • Security hackers: – Sell proprietary info to competition – Encrypt storage until pay (ransom/blackmal?) – Erase everything to damage business – DDOS, botnets attack network • Tokyo firm pay $31K to stop it – Not even clear who should pay ransom • In a cloud at the mercy of their security measures Final Observations: What’s wrong with today’s cloud security research Failure to look at reality – Many security schemes impose unrealistic overheads (e.g., >35%!!) – no one will use them in real life clouds Failure to consider economy – Security schemes would cause significant changes to existing cloud infrastructures – Many attacks simply don’t make any economic sense Lack of realistic threat models – Many papers present unrealistic threat models, (“Solutions in search of a problem”) 38 Clouds can be used for malicious purposes Adversaries can rent clouds temporarily to create a large scale botnet very quickly Clouds can be used for spamming, Denial of service, brute force password breaking, and other attacks Example: WPACracker.com – Claims to break WPA passwords for $17 in under 20 minutes, using a cloud 39 Cloud Computing...... Design for Disaster?
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