Designs and Challenges in Authenticated Encryption
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Ransomware Facts and Tips
RANSOMWARE FACTS & TIPS As technology evolves, the prevalence of ransomware attacks is growing among businesses and consumers alike. It’s important for digital citizens to be vigilant about basic digital hygiene in an increasingly connected world. WHAT IS RANSOMWARE? Ransomware is a type of malware that accesses a victim’s files, locks and encrypts them and then demands the victim to pay a ransom to get them back. Cybercriminals use these attacks to try to get users to click on attachments or links that appear legitimate but actually contain malicious code. Ransomware is like the “digital kidnapping” of valuable data – from personal photos and memories to client information, financial records and intellectual property. Any individual or organization could be a potential ransomware target. WHAT CAN YOU DO? We can all help protect ourselves – and our organizations – against ransomware and other malicious attacks by following these STOP. THINK. CONNECT. tips: • Keep all machines clean: Keep the software on all Internet-connected devices up to date. All critical software, including computer and mobile operating systems, security software and other frequently used programs and apps, should be running the most current versions. • Get two steps ahead: Turn on two-step authentication – also known as two-step verification or multi-factor authentication – on accounts where available. Two-factor authentication can use anything from a text message to your phone to a token to a biometric like your fingerprint to provide enhanced account security. • Back it up: Protect your valuable work, music, photos and other digital information by regularly making an electronic copy and storing it safely. -
The Order of Encryption and Authentication for Protecting Communications (Or: How Secure Is SSL?)?
The Order of Encryption and Authentication for Protecting Communications (Or: How Secure is SSL?)? Hugo Krawczyk?? Abstract. We study the question of how to generically compose sym- metric encryption and authentication when building \secure channels" for the protection of communications over insecure networks. We show that any secure channels protocol designed to work with any combina- tion of secure encryption (against chosen plaintext attacks) and secure MAC must use the encrypt-then-authenticate method. We demonstrate this by showing that the other common methods of composing encryp- tion and authentication, including the authenticate-then-encrypt method used in SSL, are not generically secure. We show an example of an en- cryption function that provides (Shannon's) perfect secrecy but when combined with any MAC function under the authenticate-then-encrypt method yields a totally insecure protocol (for example, ¯nding passwords or credit card numbers transmitted under the protection of such protocol becomes an easy task for an active attacker). The same applies to the encrypt-and-authenticate method used in SSH. On the positive side we show that the authenticate-then-encrypt method is secure if the encryption method in use is either CBC mode (with an underlying secure block cipher) or a stream cipher (that xor the data with a random or pseudorandom pad). Thus, while we show the generic security of SSL to be broken, the current practical implementations of the protocol that use the above modes of encryption are safe. 1 Introduction The most widespread application of cryptography in the Internet these days is for implementing a secure channel between two end points and then exchanging information over that channel. -
SHA-3 Update
SHA+3%update% %% % Quynh%Dang% Computer%Security%Division% ITL,%NIST% IETF%86% SHA-3 Competition 11/2/2007% SHA+3%CompeDDon%Began.% 10/2/2012% Keccak&announced&as&the&SHA13&winner.& IETF%86% Secure Hash Algorithms Outlook ► SHA-2 looks strong. ► We expect Keccak (SHA-3) to co-exist with SHA-2. ► Keccak complements SHA-2 in many ways. Keccak is good in different environments. Keccak is a sponge - a different design concept from SHA-2. IETF%86% Sponge Construction Sponge capacity corresponds to a security level: s = c/2. IETF%86% SHA-3 Selection ► We chose Keccak as the winner because of many different reasons and below are some of them: ► It has a high security margin. ► It received good amount of high-quality analyses. ► It has excellent hardware performance. ► It has good overall performance. ► It is very different from SHA-2. ► It provides a lot of flexibility. IETF%86% Keccak Features ► Keccak supports the same hash-output sizes as SHA-2 (i.e., SHA-224, -256, -384, -512). ► Keccak works fine with existing applications, such as DRBGs, KDFs, HMAC and digital signatures. ► Keccak offers flexibility in performance/security tradeoffs. ► Keccak supports tree hashing. ► Keccak supports variable-length output. IETF%86% Under Consideration for SHA-3 ► Support for variable-length hashes ► Considering options: ► One capacity: c = 512, with output size encoding, ► Two capacities: c = 256 and c = 512, with output size encoding, or ► Four capacities: c = 224, c = 256, c=384, and c = 512 without output size encoding (preferred by the Keccak team). ► Input format for SHA-3 hash function(s) will contain a padding scheme to support tree hashing in the future. -
Lecture9.Pdf
Merkle- Suppose H is a Damgaord hash function built from a secure compression function : several to build a function ways keyed : m : = H Ilm 1 . end FCK ) (k ) Prep key , " " ↳ - Insecure due to structure of Merkle : can mount an extension attack: H (KH m) can Barnyard given , compute ' Hlkllmllm ) by extending Merkle- Danged chain = : m : 2 . FCK ) 11k) Append key , Hlm ↳ - - to : Similar to hash then MAC construction and vulnerable same offline attack adversary finds a collision in the - - > Merkle and uses that to construct a for SHA I used PDF files Barnyard prefix forgery f , they ↳ - Structure in SHA I (can matches exploited collision demonstration generate arbitrary collisions once prefix ) ' = : FCK m - H on h 3. method , ) ( K HMH K) for reasonable randomness ( both Envelope pseudo assumptions e.g , : = - = i - - : F ( m m } : h K m h m k 4. nest ( ki ) H Ck H (k m ( , and m ( ) is a PRF both Two , kz , ) (ka HH , )) F- , ) ) Falk , ) , ) key , - of these constructions are secure PRFS on a variable size domain hash- based MAC ✓ a the - nest with correlated : HMAC is PRF / MAC based on two key (though keys) : = m H H ka m HMACCK ( K H ( , )) , ) , where k ← k ④ and kz ← k to , ipad opad and and are fixed ( in the HMAC standard) ipad opad strings specified I 0×36 repeated %x5C repeated : k . a Since , and ka are correlated need to make on h remains under Sety , stronger assumption security leg , pseudorandom related attack) Instantiations : denoted HMAC- H where H is the hash function Typically , HMAC- SHAI %" - - HMAC SHA256 -
Online Payment Fraud Prevention Using Cryptographic Algorithm TDES
S. Aishwarya et al, International Journal of Computer Science and Mobile Computing, Vol.4 Issue.4, April- 2015, pg. 317-323 Available Online at www.ijcsmc.com International Journal of Computer Science and Mobile Computing A Monthly Journal of Computer Science and Information Technology ISSN 2320–088X IJCSMC, Vol. 4, Issue. 4, April 2015, pg.317 – 323 RESEARCH ARTICLE Online Payment Fraud Prevention Using Cryptographic Algorithm TDES S. AISHWARYA1 K.DEVIKA RANI DHIVYA*2 III MSc (SS), Assistant Professor, Department of CA & SS, Department of CA & SS, Sri Krishna Arts and Science College, Sri Krishna Arts and Science College, Coimbatore, Tamil Nadu, Coimbatore, Tamil Nadu, India India ABSTRACT: Credit card is a small plastic card issued by a bank, building society, etc., allowing the holder to purchase goods or services on credit. Debit card is a card allowing the holder to transfer money electronically from their bank account when making a purchase. The use of credit cards and debit cards are increasing day by day. People are relying more on both cards nowadays than in the previous days. As credit cards and debit cards becomes the most popular mode of payment for both online as well as regular purchase, cases of fraud associated with it are also rising. In real life, fraudulent transactions are scattered with genuine transactions and simple pattern matching techniques are not often sufficient to detect those frauds accurately. In this project the process of Cryptography has been followed, it is one of the most important security technologies which used to secure the data transmission and the data itself. -
Ransomware Is Here: What You Can Do About It?
WHITEPAPER Ransomware is Here: What you can do about it? Overview Over the last few years, ransomware has emerged as one of the most devastating and costly attacks in the hacker arsenal. Cyber thieves are increasingly using this form of attack to target individuals, corporate entities and public sector organizations alike by holding your system or files for ransom. Unlike other forms of cyber theft that often involve stolen financial or healthcare information, ransomware cuts out the middleman. In cases where an attacker steals health or financial documents, they must sell them on to third parties to make money. As far as ransomware is concerned, the money comes directly from the victim. Ransomware is a quickly growing threat vector. According to the FBI’s Internet Crime Complaint center (IC3), infected users made complaints about ransomware 2,453 times in 2015—nearly double the figure for 2014. What’s more, these figures most likely represent only the tip of the iceberg, as many users pay their ransom without making a report to the authorities. A recent survey conducted by a Cyber Security Research Center at the University of Kent found that over 40% of those infected with CryptoLocker actually agreed to pay the ransom demanded, which is a big incentive for hackers to target more systems. Lastly, hackers are rapidly iterating both malware and distribution techniques. In early Q2 of 2016, a new variant of ransomware, known as CryptXXX, emerged on the scene. This program is packed in such a way that users and antivirus software may initially confuse it for a Windows DLL file. -
GCM) for Confidentiality And
NIST Special Publication 800-38D Recommendation for Block DRAFT (April, 2006) Cipher Modes of Operation: Galois/Counter Mode (GCM) for Confidentiality and Authentication Morris Dworkin C O M P U T E R S E C U R I T Y Abstract This Recommendation specifies the Galois/Counter Mode (GCM), an authenticated encryption mode of operation for a symmetric key block cipher. KEY WORDS: authentication; block cipher; cryptography; information security; integrity; message authentication code; mode of operation. i Table of Contents 1 PURPOSE...........................................................................................................................................................1 2 AUTHORITY.....................................................................................................................................................1 3 INTRODUCTION..............................................................................................................................................1 4 DEFINITIONS, ABBREVIATIONS, AND SYMBOLS.................................................................................2 4.1 DEFINITIONS AND ABBREVIATIONS .............................................................................................................2 4.2 SYMBOLS ....................................................................................................................................................4 4.2.1 Variables................................................................................................................................................4 -
Security, Encryption, and Certificates FAQ
Security, Encryption, and Certificates FAQ Overview In Security Center 5.4, several new capabilities will be added that further strengthen the security of the platform itself, as well as the privacy of data. The aim is to prevent unauthorized access to stored and transmitted messages and data, as well as prevent attacks through the use of stronger encryption and authentication mechanisms. With growing demand for privacy, new capabilities in Security Center 5.4 will strengthen Genetec’s position and overall value proposition. This FAQ addresses some of the most common questions in relation to the new capabilities of Security Center: Encryption, Authentication, and Digital Certificates. These concepts are first described in generic terms; the FAQ then outlines how these new measures are used within Security Center 5.4. Encryption vs. Authentication vs. Authorization What is the difference between encryption, authentication, and authorization? Encryption is used to encrypt data so that only authorized users can see it. Authentication determines whether an entity is who they claim to be, eg. in the case of an individual, it is usually based on a username/password combination. Authentication does not actually say anything about what someone is authorized to do or has the right to do. o Client-side authentication uses username/password combinations, tokens (dual authentication), and other techniques. o Server-side authentication uses certificates to identify trusted third parties. Authorization is the function of specifying the rights, eg. defining the access rights someone has over a set of recourses such as a private data, computing resources, or an application. When users log into a Security Center system, what they are allowed or authorized to do depends on the set of privileges assigned to them by administrators. -
Biometrics Authentication Technique for Intrusion Detection Systems Using Fingerprint Recognition
International Journal of Computer Science, Engineering and Information Technology (IJCSEIT), Vol.2, No.1, February 2012 BIOMETRICS AUTHENTICATION TECHNIQUE FOR INTRUSION DETECTION SYSTEMS USING FINGERPRINT RECOGNITION 1 2 3 Smita S. Mudholkar , Pradnya M. Shende , Milind V. Sarode 1, 2& 3 Department of Computer Science & Engineering, Amravati University, India [email protected], [email protected], [email protected] ABSTRACT Identifying attackers is a major apprehension to both organizations and governments. Recently, the most used applications for prevention or detection of attacks are intrusion detection systems. Biometrics technology is simply the measurement and use of the unique characteristics of living humans to distinguish them from one another and it is more useful as compare to passwords and tokens as they can be lost or stolen so we have choose the technique biometric authentication. The biometric authentication provides the ability to require more instances of authentication in such a quick and easy manner that users are not bothered by the additional requirements. In this paper, we have given a brief introduction about biometrics. Then we have given the information regarding the intrusion detection system and finally we have proposed a method which is based on fingerprint recognition which would allow us to detect more efficiently any abuse of the computer system that is running. KEYWORDS Intrusion detection, keystroke, Biometrics, Mouse dynamics, Authentication 1. INTRODUCTION Biometric recognition forms a strong bond between a person and his identity as biometric traits cannot be easily shared, lost, or duplicated. Hence, biometric recognition is fundamentally superior and more resistant to social engineering attacks than the two conservative methods of recognition, namely, passwords and tokens. -
Secure by Design, Secure by Default: Requirements and Guidance
Biometrics and Surveillance Camera Commissioner Secure by Design, Secure by Default Video Surveillance Products Introduction This guidance is for any organisation manufacturing Video Surveillance Systems (VSS), or manufacturing or assembling components intended to be utilised as part of a VSS. It is intended to layout the Biometrics and Surveillance Camera Commissioners (BSCC) minimum requirements to ensure such systems are designed and manufactured in a manner that assures they are Secure by Design. It also contains certain component requirements that will ensure a configuration that is Secure by Default when the component is shipped, thereby making it more likely that the system will be installed and left in a secure state. This guidance forms part of a wider suite of documentation being developed as part of the SCC Strategy, in support of the SCC Code of Practice. Background and Context The nature of the Internet means that connected devices can be subjected to a cyber attack from anywhere in the world. Widespread attacks on connected products is a current and real threat, and a number of highly publicised attacks have already occurred. The Mirai malware targeted devices such as internet-enabled cameras (IP cameras). Mirai was successful because it exploited the use of common default credentials (such as a username and password being set by the manufacturer as ‘admin’) and poor security configuration of devices. Ultimately, this facilitated attacks on a range of commercial and social media services and included an outage of streaming services such as Netflix. An evolution of Mirai, called Reaper, has also been discovered. Reaper used publicly and easily available exploits that remained unfixed (patched) and highlighted the problem around non patching of known security vulnerabilities, allowing attackers to utilise them to cause harm. -
Speeding up OMD Instantiations in Hardware
Speeding Up OMD Instantiations in Hardware Diana Maimuţ1[0000−0002−9541−5705] and Alexandru Ştefan Mega1,2[0000−0002−9541−1114] 1 Advanced Technologies Institute 10 Dinu Vintilă, Bucharest, Romania {diana.maimut,ati}@dcti.ro 2 Politehnica University of Bucharest Bucharest, Romania [email protected] Abstract. Particular instantiations of the Offset Merkle Damgård au- thenticated encryption scheme (OMD) represent highly secure alterna- tives for AES-GCM. It is already a fact that OMD can be efficiently implemented in software. Given this, in our paper we focus on speeding- up OMD in hardware, more precisely on FPGA platforms. Thus, we propose a new OMD instantiation based on the compression function of BLAKE2b. Moreover, to the best of our knowledge, we present the first FPGA implementation results for the SHA-512 instantiation of OMD as well as the first architecture of an online authenticated encryption system based on OMD. Keywords: Authenticated encryption, pseudorandom function, compression function, provable security, FPGA, hardware optimization, nonce respecting ad- versaries. 1 Introduction Authenticated encryption (AE) primitives ensure both message confidentiality and authenticity. Initially, AE algorithms achieved confidentiality and integrity by combining two distinct cryptographic primitives (one for each of the two goals). Around two decades ago the perspective of having a unique primitive for confidentiality and integrity started to appear. Rogaway [16] extended AE schemes by adding a new type of input for associated data (AD) and, thus, AEAD (authenticated encryption with associated data) was the next step. Such a model is helpful in real world scenario in which part of the message (e.g. a header) needs only to be authenticated. -
Authorization: Intrusion Detection Prof
CS 166: Information Security Authorization: Intrusion Detection Prof. Tom Austin San José State University Prevention vs. Detection • Most systems we've discussed focus on keeping the bad guys out. • Intrusion prevention is a traditional focus of computer security: – Authentication – Firewalls – Virus Intrusion Detection • Despite defenses, bad guys will sometimes get in. • Intrusion detection systems (IDS) –Detect attacks in progress –Look for unusual/suspicious activity • IDS evolved from log file analysis Who is a likely intruder? An intruder might be an outsider who got through your firewall… …or an angry insider. What do intruders do? • Launch attacks that are –well-known –slight variations on known attacks –previously unseen • “Borrow” system resources –perhaps to attack another system IDS • Intrusion detection architectures –Host-based IDS –Network-based IDS • Intrusion detection approaches –Signature-based IDS –Anomaly-based IDS Host-Based IDS • Monitor activities on hosts for –Known attacks –Suspicious behavior • Designed to detect attacks such as –Buffer overflow –Escalation of privilege, … • Little or no view of network activities Network-Based IDS • Monitor activity on the network for… –Known attacks –Suspicious network activity • Designed to detect attacks such as –Denial of service –Network probes –Malformed packets, etc. • Some overlap with firewall • Little or no view of host-based attacks Signature detection Signature detection looks for known attack patterns • Low false positives • Unable to handle unknown attack patterns