Cryptographic Communication and Authentication
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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. -
An Advance Visual Model for Animating Behavior of Cryptographic Protocols
An Advance Visual Model for Animating Behavior of Cryptographic Protocols Mabroka Ali Mayouf Maeref1*, Fatma Alghali2, Khadija Abied2 1 Sebha University, Faculty of Science, Department of Computer Science, P. O. Box 18758 Sebha, Libya, Libyan. 2 Sebha University of Libya, Sebha, Libya. * Corresponding author. Tel.: 00218-925132935; email: [email protected] Manuscript submitted February 13, 2015; accepted July 5, 2015. doi: 10.17706/jcp.10.5.336-346 Abstract: Visual form description benefits from the ability of visualization to provide precise and clear description of object behavior especially if the visual form is extracted from the real world. It provides clear definition of object and the behavior of that object. Although the current descriptions of cryptographic protocol components and operations use a different visual representation, the cryptographic protocols behaviors are not actually reflected. This characteristic is required and included within our proposed visual model. The model uses visual form and scenario-based approach for describing cryptographic protocol behavior and thus increasing the ability to describe more complicated protocol in a simple and easy way. Key words: Animation, cryptographic protocols, interactive tool, visualization. 1. Introduction Cryptographic protocols (CPs) mostly combine both theory and practice [1], [2]. These cause protocol complexity describing and understanding. Therefore, separating the mathematical part from the protocol behavior should provide feeling of how the protocol works, thus increasing the ability to describe and to gain confidence in reflecting more complicated information about CPs, as well as to generate interest to know about other more complex protocol concepts. Several researchers realized the use of visual model and animation techniques to reflect the explanation of the learning objectives and their benefits [3]-[11]. -
A Quantitative Study of Advanced Encryption Standard Performance
United States Military Academy USMA Digital Commons West Point ETD 12-2018 A Quantitative Study of Advanced Encryption Standard Performance as it Relates to Cryptographic Attack Feasibility Daniel Hawthorne United States Military Academy, [email protected] Follow this and additional works at: https://digitalcommons.usmalibrary.org/faculty_etd Part of the Information Security Commons Recommended Citation Hawthorne, Daniel, "A Quantitative Study of Advanced Encryption Standard Performance as it Relates to Cryptographic Attack Feasibility" (2018). West Point ETD. 9. https://digitalcommons.usmalibrary.org/faculty_etd/9 This Doctoral Dissertation is brought to you for free and open access by USMA Digital Commons. It has been accepted for inclusion in West Point ETD by an authorized administrator of USMA Digital Commons. For more information, please contact [email protected]. A QUANTITATIVE STUDY OF ADVANCED ENCRYPTION STANDARD PERFORMANCE AS IT RELATES TO CRYPTOGRAPHIC ATTACK FEASIBILITY A Dissertation Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Computer Science By Daniel Stephen Hawthorne Colorado Technical University December, 2018 Committee Dr. Richard Livingood, Ph.D., Chair Dr. Kelly Hughes, DCS, Committee Member Dr. James O. Webb, Ph.D., Committee Member December 17, 2018 © Daniel Stephen Hawthorne, 2018 1 Abstract The advanced encryption standard (AES) is the premier symmetric key cryptosystem in use today. Given its prevalence, the security provided by AES is of utmost importance. Technology is advancing at an incredible rate, in both capability and popularity, much faster than its rate of advancement in the late 1990s when AES was selected as the replacement standard for DES. Although the literature surrounding AES is robust, most studies fall into either theoretical or practical yet infeasible. -
Symmetric Asynchronous Ratcheted Communication with Associated Data
Symmetric Asynchronous Ratcheted Communication with Associated Data B Hailun Yan( ) and Serge Vaudenay Ecole´ Polytechnique F´ed´erale de Lausanne (EPFL), Lausanne, Switzerland {hailun.yan,serge.vaudenay}@epfl.ch Abstract. Following up mass surveillance and privacy issues, modern secure communication protocols now seek strong security, such as forward secrecy and post-compromise security, in the face of state exposures. To address this problem, ratcheting was thereby introduced, widely used in real-world messaging protocols like Signal. However, ratcheting comes with a high cost. Recently, Caforio et al. proposed pragmatic construc- tions which compose a weakly secure “light” protocol and a strongly secure “heavy” protocol, in order to achieve the so-called ratcheting on demand. The light protocol they proposed has still a high complexity. In this paper, we prove the security of the lightest possible proto- col we could imagine, which essentially encrypts then hashes the secret key. We prove it without any random oracle by introducing a new secu- rity notion in the standard model. Our protocol composes well with the generic transformation techniques by Caforio et al. to offer high security and performance at the same time. 1 Introduction A classic communication model usually assumes that the endpoints are secure while the adversary is on the communication channel. However, protocols in recent messaging applications are secured with end-to-end encryption due to the prevalence of malware and system vulnerabilities. They attempt to enable secure communication services by regularly updating (ratcheting) the encryption key. One notable example of ratcheting is the Signal protocol [14] by Open Whisper Systems with its double-ratchet algorithm. -
2012 07 26 Letter to Skype
! Privacy International 46 Bedford Row London WC1R 4LR United Kingdom +44 (0) 20 7242 2836 @privacyint UK Charity No. 1147471 Friday, 27 July 2012 Dear Mr Bates, I am writing to request further information about the privacy implications of recent developments at Skype, as reported in the Washington Post.1 We were delighted to read that you believe these reports are “inaccurate” and“could mislead the Skype community”, and that you want to “clear this up”. 2 The growth of Skype since its launch in 2003 to become the world's leading VoIP provider has been driven by service that is affordable, high quality and, above all, secure. From an early stage in its development, Skype has assured its customers of the security of their communications. Press releases and product descriptions from 2005 boast of "end-to-end encryption for superior privacy" that "nobody can intercept".3 In 2008, a spokesperson reassured users that “[w]e have not received any subpoenas or court orders asking us to perform a live interception or wiretap of Skype-to-Skype communications” and “[i]n any event, because of Skype's peer-to-peer architecture and encryption techniques, Skype would not be able to comply with such a request”.4 In short, a promise was made to Skype customers that the privacy of their conversations and file transfers would be protected. As I'm sure you know, among Skype's 663 million registered users across the world are human rights defenders and pro-democracy activists living under autocratic regimes. In an environment where most channels of communication -
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. -
Constructing Low-Weight Dth-Order Correlation-Immune Boolean Functions Through the Fourier-Hadamard Transform Claude Carlet and Xi Chen*
1 Constructing low-weight dth-order correlation-immune Boolean functions through the Fourier-Hadamard transform Claude Carlet and Xi Chen* Abstract The correlation immunity of Boolean functions is a property related to cryptography, to error correcting codes, to orthogonal arrays (in combinatorics, which was also a domain of interest of S. Golomb) and in a slightly looser way to sequences. Correlation-immune Boolean functions (in short, CI functions) have the property of keeping the same output distribution when some input variables are fixed. They have been widely used as combiners in stream ciphers to allow resistance to the Siegenthaler correlation attack. Very recently, a new use of CI functions has appeared in the framework of side channel attacks (SCA). To reduce the cost overhead of counter-measures to SCA, CI functions need to have low Hamming weights. This actually poses new challenges since the known constructions which are based on properties of the Walsh-Hadamard transform, do not allow to build unbalanced CI functions. In this paper, we propose constructions of low-weight dth-order CI functions based on the Fourier- Hadamard transform, while the known constructions of resilient functions are based on the Walsh-Hadamard transform. We first prove a simple but powerful result, which makes that one only need to consider the case where d is odd in further research. Then we investigate how constructing low Hamming weight CI functions through the Fourier-Hadamard transform (which behaves well with respect to the multiplication of Boolean functions). We use the characterization of CI functions by the Fourier-Hadamard transform and introduce a related general construction of CI functions by multiplication. -
On the NIST Lightweight Cryptography Standardization
On the NIST Lightweight Cryptography Standardization Meltem S¨onmez Turan NIST Lightweight Cryptography Team ECC 2019: 23rd Workshop on Elliptic Curve Cryptography December 2, 2019 Outline • NIST's Cryptography Standards • Overview - Lightweight Cryptography • NIST Lightweight Cryptography Standardization Process • Announcements 1 NIST's Cryptography Standards National Institute of Standards and Technology • Non-regulatory federal agency within U.S. Department of Commerce. • Founded in 1901, known as the National Bureau of Standards (NBS) prior to 1988. • Headquarters in Gaithersburg, Maryland, and laboratories in Boulder, Colorado. • Employs around 6,000 employees and associates. NIST's Mission to promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life. 2 NIST Organization Chart Laboratory Programs Computer Security Division • Center for Nanoscale Science and • Cryptographic Technology Technology • Secure Systems and Applications • Communications Technology Lab. • Security Outreach and Integration • Engineering Lab. • Security Components and Mechanisms • Information Technology Lab. • Security Test, Validation and • Material Measurement Lab. Measurements • NIST Center for Neutron Research • Physical Measurement Lab. Information Technology Lab. • Advanced Network Technologies • Applied and Computational Mathematics • Applied Cybersecurity • Computer Security • Information Access • Software and Systems • Statistical -
Ohio IT Standard ITS-SEC-01 Data Encryption and Cryptography
Statewide Standard State of Ohio IT Standard Standard Number: Title: ITS-SEC-01 Data Encryption and Cryptography Effective Date: Issued By: 03/12/2021 Ervan D. Rodgers II, Assistant Director/State Chief Information Officer Office of Information Technology Ohio Department of Administrative Services Version Identifier: Published By: 2.0 Investment and Governance Division Ohio Office of Information Technology 1.0 Purpose This state IT standard defines the minimum requirements for cryptographic algorithms that are cryptographically strong and are used in security services that protect at-risk or sensitive data as defined and required by agency or State policy, standard or rule. This standard does not classify data elements; does not define the security schemes and mechanisms for devices such as tape backup systems, storage systems, mobile computers or removable media; and does not identify or approve secure transmission protocols that may be used to implement security requirements. 2.0 Scope Pursuant to Ohio Administrative Policy IT-01, “Authority of the State Chief Information Officer to Establish Ohio IT Policy,” this state IT standard is applicable to every organized body, office, or agency established by the laws of the state for the exercise of any function of state government except for those specifically exempted. 3.0 Background The National Institute for Science and Technology (NIST) conducts extensive research and development in cryptography techniques. Their publications include technical standards for data encryption, digital signature and message authentication as well as guidelines for implementing information security and managing cryptographic keys. These standards and guidelines have been mandated for use in federal agencies and adopted by state governments and private enterprises. -
Security + Encryption Standards
Security + Encryption Standards Author: Joseph Lee Email: joseph@ ripplesoftware.ca Mobile: 778-725-3206 General Concepts Forward secrecy / perfect forward secrecy • Using a key exchange to provide a new key for each session provides improved forward secrecy because if keys are found out by an attacker, past data cannot be compromised with the keys Confusion • Cipher-text is significantly different than the original plaintext data • The property of confusion hides the relationship between the cipher-text and the key Diffusion • Is the principle that small changes in message plaintext results in large changes in the cipher-text • The idea of diffusion is to hide the relationship between the cipher-text and the plaintext Secret-algorithm • A proprietary algorithm that is not publicly disclosed • This is discouraged because it cannot be reviewed Weak / depreciated algorithms • An algorithm that can be easily "cracked" or defeated by an attacker High-resiliency • Refers to the strength of the encryption key if an attacker discovers part of the key Data-in-transit • Data sent over a network Data-at-rest • Data stored on a medium Data-in-use • Data being used by an application / computer system Out-of-band KEX • Using a medium / channel for key-exchange other than the medium the data transfer is taking place (phone, email, snail mail) In-band KEX • Using the same medium / channel for key-exchange that the data transfer is taking place Integrity • Ability to determine the message has not been altered • Hashing algorithms manage Authenticity -
TS 102 176-1 V2.1.1 (2011-07) Technical Specification
ETSI TS 102 176-1 V2.1.1 (2011-07) Technical Specification Electronic Signatures and Infrastructures (ESI); Algorithms and Parameters for Secure Electronic Signatures; Part 1: Hash functions and asymmetric algorithms 2 ETSI TS 102 176-1 V2.1.1 (2011-07) Reference RTS/ESI-000080-1 Keywords e-commerce, electronic signature, security ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://portal.etsi.org/tb/status/status.asp If you find errors in the present document, please send your comment to one of the following services: http://portal.etsi.org/chaircor/ETSI_support.asp Copyright Notification No part may be reproduced except as authorized by written permission. -
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.