SSL Checklist for Pentesters
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Secure Shell- Its Significance in Networking (Ssh)
International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: [email protected] Volume 4, Issue 3, March 2015 ISSN 2319 - 4847 SECURE SHELL- ITS SIGNIFICANCE IN NETWORKING (SSH) ANOOSHA GARIMELLA , D.RAKESH KUMAR 1. B. TECH, COMPUTER SCIENCE AND ENGINEERING Student, 3rd year-2nd Semester GITAM UNIVERSITY Visakhapatnam, Andhra Pradesh India 2.Assistant Professor Computer Science and Engineering GITAM UNIVERSITY Visakhapatnam, Andhra Pradesh India ABSTRACT This paper is focused on the evolution of SSH, the need for SSH, working of SSH, its major components and features of SSH. As the number of users over the Internet is increasing, there is a greater threat of your data being vulnerable. Secure Shell (SSH) Protocol provides a secure method for remote login and other secure network services over an insecure network. The SSH protocol has been designed to support many features along with proper security. This architecture with the help of its inbuilt layers which are independent of each other provides user authentication, integrity, and confidentiality, connection- oriented end to end delivery, multiplexes encrypted tunnel into several logical channels, provides datagram delivery across multiple networks and may optionally provide compression. Here, we have also described in detail what every layer of the architecture does along with the connection establishment. Some of the threats which Ssh can encounter, applications, advantages and disadvantages have also been mentioned in this document. Keywords: SSH, Cryptography, Port Forwarding, Secure SSH Tunnel, Key Exchange, IP spoofing, Connection- Hijacking. 1. INTRODUCTION SSH Secure Shell was first created in 1995 by Tatu Ylonen with the release of version 1.0 of SSH Secure Shell and the Internet Draft “The SSH Secure Shell Remote Login Protocol”. -
Fast Elliptic Curve Cryptography in Openssl
Fast Elliptic Curve Cryptography in OpenSSL Emilia K¨asper1;2 1 Google 2 Katholieke Universiteit Leuven, ESAT/COSIC [email protected] Abstract. We present a 64-bit optimized implementation of the NIST and SECG-standardized elliptic curve P-224. Our implementation is fully integrated into OpenSSL 1.0.1: full TLS handshakes using a 1024-bit RSA certificate and ephemeral Elliptic Curve Diffie-Hellman key ex- change over P-224 now run at twice the speed of standard OpenSSL, while atomic elliptic curve operations are up to 4 times faster. In ad- dition, our implementation is immune to timing attacks|most notably, we show how to do small table look-ups in a cache-timing resistant way, allowing us to use precomputation. To put our results in context, we also discuss the various security-performance trade-offs available to TLS applications. Keywords: elliptic curve cryptography, OpenSSL, side-channel attacks, fast implementations 1 Introduction 1.1 Introduction to TLS Transport Layer Security (TLS), the successor to Secure Socket Layer (SSL), is a protocol for securing network communications. In its most common use, it is the \S" (standing for \Secure") in HTTPS. Two of the most popular open- source cryptographic libraries implementing SSL and TLS are OpenSSL [19] and Mozilla Network Security Services (NSS) [17]: OpenSSL is found in, e.g., the Apache-SSL secure web server, while NSS is used by Mozilla Firefox and Chrome web browsers, amongst others. TLS provides authentication between connecting parties, as well as encryp- tion of all transmitted content. Thus, before any application data is transmit- ted, peers perform authentication and key exchange in a TLS handshake. -
Dynamic Public Key Certificates with Forward Secrecy
electronics Article Dynamic Public Key Certificates with Forward Secrecy Hung-Yu Chien Department of Information Management, National Chi Nan University, Nantou 54561, Taiwan; [email protected] Abstract: Conventionally, public key certificates bind one subject with one static public key so that the subject can facilitate the services of the public key infrastructure (PKI). In PKI, certificates need to be renewed (or revoked) for several practical reasons, including certificate expiration, private key breaches, condition changes, and possible risk reduction. The certificate renewal process is very costly, especially for those environments where online authorities are not available or the connection is not reliable. A dynamic public key certificate (DPKC) facilitates the dynamic changeover of the current public–private key pairs without renewing the certificate authority (CA). This paper extends the previous study in several aspects: (1) we formally define the DPKC; (2) we formally define the security properties; (3) we propose another implementation of the Krawczyk–Rabin chameleon-hash- based DPKC; (4) we propose two variants of DPKC, using the Ateniese–Medeiros key-exposure-free chameleon hash; (5) we detail two application scenarios. Keywords: dynamic public key certificate; chameleon signature; certificate renewal; wireless sensor networks; perfect forward secrecy 1. Introduction Citation: Chien, H.-Y. Dynamic Certificates act as the critical tokens in conventional PKI systems. With the trust Public Key Certificates with Forward of the CA, a -
You Really Shouldn't Roll Your Own Crypto: an Empirical Study of Vulnerabilities in Cryptographic Libraries
You Really Shouldn’t Roll Your Own Crypto: An Empirical Study of Vulnerabilities in Cryptographic Libraries Jenny Blessing Michael A. Specter Daniel J. Weitzner MIT MIT MIT Abstract A common aphorism in applied cryptography is that cryp- The security of the Internet rests on a small number of open- tographic code is inherently difficult to secure due to its com- source cryptographic libraries: a vulnerability in any one of plexity; that one should not “roll your own crypto.” In par- them threatens to compromise a significant percentage of web ticular, the maxim that complexity is the enemy of security traffic. Despite this potential for security impact, the character- is a common refrain within the security community. Since istics and causes of vulnerabilities in cryptographic software the phrase was first popularized in 1999 [52], it has been in- are not well understood. In this work, we conduct the first voked in general discussions about software security [32] and comprehensive analysis of cryptographic libraries and the vul- cited repeatedly as part of the encryption debate [26]. Conven- nerabilities affecting them. We collect data from the National tional wisdom holds that the greater the number of features Vulnerability Database, individual project repositories and in a system, the greater the risk that these features and their mailing lists, and other relevant sources for eight widely used interactions with other components contain vulnerabilities. cryptographic libraries. Unfortunately, the security community lacks empirical ev- Among our most interesting findings is that only 27.2% of idence supporting the “complexity is the enemy of security” vulnerabilities in cryptographic libraries are cryptographic argument with respect to cryptographic software. -
Sicherheit in Kommunikationsnetzen (Network Security)
Sicherheit in Kommunikationsnetzen (Network Security) Transport Layer Security Dr.-Ing. Matthäus Wander Universität Duisburg-Essen Transport Layer Security (TLS) PrivateTLS data Web browser Web server ∙ Cryptographic protocol ∘ Provides security on top of reliable transport (TCP) ∘ Used to secure HTTP, SMTP, IMAP, XMPP and others ∙ Security goals ∘ Authentication of server and optionally client ∘ Data integrity (no manipulation of data) ∘ Confidentiality (encryption) Universität Duisburg-Essen Matthäus Wander 2 Verteilte Systeme History ∙ Predecessor: Secure Sockets Layer (SSL) ∘ Developed by Netscape for HTTPS (= HTTP + SSL) ∙ 1994: SSL 2.0 ∘ Insecure, major security weaknesses ∙ 1995: SSL 3.0 ∘ Insecure, deprecated since 2015 (RFC 7568) ∙ 1999: TLS 1.0, minor improvements to SSL 3.0 ∘ Standardization and further development by IETF Universität Duisburg-Essen Matthäus Wander 3 Verteilte Systeme History ∙ 2003: TLS Extensions ∘ New features or security mechanisms (e.g. Encrypt-then-MAC, RFC 7366) ∙ 2006: TLS 1.1 ∘ Security improvements ∙ 2008: TLS 1.2 Presented in this lecture ∘ Added new or replaced old cryptographic algorithms ∙ TLS 1.3 is work in progress as of 2017 ∘ Outlook: new handshake and other major changes Universität Duisburg-Essen Matthäus Wander 4 Verteilte Systeme Protocol Overview Application Layer (e.g. HTTP) Handshake Change Cipher Application Alert Protocol Protocol Spec Protocol Data Protocol Record Protocol Transport Layer (e.g. TCP) ∙ TLS consists of two layers: ∘ Handshake Protocol and other protocols ∘ Record Protocol -
Security Economics in the HTTPS Value Chain
Security Economics in the HTTPS Value Chain Hadi Asghari*, Michel J.G. van Eeten*, Axel M. Arnbak+ & Nico A.N.M. van Eijk+1 * [email protected], [email protected] Delft University of Technology, Faculty of Technology Policy and Management + [email protected], [email protected] University van Amsterdam, Faculty of Law, Institute for Information Law Abstract. Even though we increasingly rely on HTTPS to secure Internet communications, several landmark incidents in recent years have illustrated that its security is deeply flawed. We present an extensive multi-disciplinary analysis that examines how the systemic vulnerabilities of the HTTPS authentication model could be addressed. We conceptualize the security issues from the perspective of the HTTPS value chain. We then discuss the breaches at several Certificate Authorities (CAs). Next, we explore the security incentives of CAs via the empirical analysis of the market for SSL certificates, based on the SSL Observatory dataset. This uncovers a surprising pattern: there is no race to the bottom. Rather, we find a highly concentrated market with very large price differences among suppliers and limited price competition. We explain this pattern and explore what it tells us about the security incentives of CAs, including how market leaders seem to benefit from the status quo. In light of these findings, we look at regulatory and technical proposals to address the systemic vulnerabilities in the HTTPS value chain, in particular the EU eSignatures proposal that seeks to strictly regulate HTTPS communications. Keywords: HTTPS, Cybersecurity, Internet Governance, Constitutional Values, E-Commerce, Value Chain Analysis, Security Economics, eSignatures Regulation, SSL, TLS, Digital Certificates, Certificate Authorities. -
Prying Open Pandora's Box: KCI Attacks Against
Prying open Pandora’s box: KCI attacks against TLS Clemens Hlauschek, Markus Gruber, Florian Fankhauser, Christian Schanes RISE – Research Industrial Systems Engineering GmbH {clemens.hlauschek, markus.gruber, florian.fankhauser, christian.schanes}@rise-world.com Abstract and implementations of the protocol: their utility is ex- tremely limited, their raison d’ˆetre is practically nil, and Protection of Internet communication is becoming more the existence of these insecure key agreement options common in many products, as the demand for privacy only adds to the arsenal of attack vectors against cryp- in an age of state-level adversaries and crime syndi- tographically secured communication on the Internet. cates is steadily increasing. The industry standard for doing this is TLS. The TLS protocol supports a multi- 1 Introduction tude of key agreement and authentication options which provide various different security guarantees. Recent at- The TLS protocol [1, 2, 3] is probably the most tacks showed that this plethora of cryptographic options widely used cryptographic protocol on the Internet. in TLS (including long forgotten government backdoors, It is designed to secure the communication between which have been cunningly inserted via export restric- client/server applications against eavesdropping, tamper- tion laws) is a Pandora’s box, waiting to be pried open by ing, and message forgery, and it also provides additional, heinous computer whizzes. Novel attacks lay hidden in optional security properties such as client authentica- plainsight. Parts of TLS areso oldthat theirfoul smell of tion. TLS is an historically grown giant: its predecessor, rot cannot be easily distinguished from the flowery smell SSL [4,5], was developed more than 20 years ago. -
An Analysis of the Transport Layer Security Protocol
An Analysis of the Transport Layer Security Protocol Thyla van der Merwe Thesis submitted to the University of London for the degree of Doctor of Philosophy Information Security Group School of Mathematics and Information Security Royal Holloway, University of London 2018 Declaration These doctoral studies were conducted under the supervision of Professor Kenneth G. Paterson. The work presented in this thesis is the result of original research I conducted, in collabo- ration with others, whilst enrolled in the School of Mathematics and Information Security as a candidate for the degree of Doctor of Philosophy. This work has not been submitted for any other degree or award in any other university or educational establishment. Thyla van der Merwe March, 2018 2 Dedication To my niece, Emma. May you always believe in your abilities, no matter what anybody tells you, and may you draw on the strength of our family for support, as I have done (especially your Gogo, she’s one tough lady). “If you’re going through hell, keep going.” Winston Churchill 3 Abstract The Transport Layer Security (TLS) protocol is the de facto means for securing commu- nications on the World Wide Web. Originally developed by Netscape Communications, the protocol came under the auspices of the Internet Engineering Task Force (IETF) in the mid 1990s and today serves millions, if not billions, of users on a daily basis. The ubiquitous nature of the protocol has, especially in recent years, made the protocol an attractive target for security researchers. Since the release of TLS 1.2 in 2008, the protocol has suffered many high-profile, and increasingly practical, attacks. -
The Heartbleed Bug: an Open Secure Sockets Layer Vulnerability
International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Impact Factor (2012): 3.358 The Heartbleed Bug: An Open Secure Sockets Layer Vulnerability Thabiso Peter Mpofu1, Noe Elisa2, Nicholaus Gati3 1M. Tech. Student, Department of Computer Science, School of IT, Jawaharlal Nehru Technological University Hyderabad, India 2, 3M. Tech. Student, Department of Computer Networks and Information Security, School of IT, Jawaharlal Nehru Technological University Hyderabad, India 3M. Tech Student, Department of Computer Networks and Information Security, School of IT, Jawaharlal Nehru Technological University Hyderabad, India, Abstract: The Open Secure Sockets Layer (OpenSSL) is used to provide a secure platform for transactions that happen over the internet. About two thirds of the servers on the internet use the OpenSSL platform to provide secure transaction over the internet. The OpenSSL is a widely used open source implementation of the Secure Sockets Layer (SSL) and Transport Layer Security (TLS). Transactions such as online shopping, emails and online banking are carried out on the internet through the OpenSSL and other platforms which provide a security. Vulnerabilities have however been found in the OpenSSL that has resulted in a wide public outcry all over the world. A vulnerability referred to as the Heartbleed Bug has sent shockwaves all over the internet. From the study we conducted, the scope of the data that has been potentially compromised is astronomical and includes usernames, passwords, bank account and credit card numbers, medical data, documents in online cloud storage. Not only has all of this user data been directly compromised, but, what are worse, the private keys of the servers running the vulnerable versions of OpenSSL were also almost certainly compromised. -
IT Security Guidelines for Transport Layer Security (TLS)
IT Security Guidelines for Transport Layer Security (TLS) National Cyber Security Centre The National Cyber Security Centre (NCSC), in collaboration with The following organizations and individuals have provided the business community, government bodies and academics, is valuable contributions: working to increase the ability of Dutch society to defend itself in - Autoriteit Persoonsgegevens the digital domain. - Belastingdienst - Centric The NCSC supports the central government and organisations in - Dienst Publiek en Communicatie the critical infrastructure sectors by providing them with expertise - Forum Standaardisatie and advice, incident response and with actions to strengthen crisis - IBD management. In addition, the NCSC provides information and - KPN advice to citizens, the government and the business community - NLnet Labs relating to awareness and prevention. The NCSC thus constitutes - Northwave the central reporting and information point for IT threats and - Platform Internetstandaarden security incidents. - RDW - SURFnet These IT Security Guidelines for Transport Layer Security were frst - de Volksbank published by the NCSC in 2014. This update (v2.1) was published in - Z-CERT 2021. See the appendix Changes to these guidelines for more details. - Daniel Kahn Gillmor, ACLU This publication was produced in collaboration with the following - Tanja Lange, Eindhoven University of Technology partners: - Kenny Paterson, ETH Zurich - the national communication security agency (NBV), part of the - Rich Salz, Akamai Technologies general -
Forward Secrecy of SPAKE2
Forward Secrecy of SPAKE2 Jos´eBecerra, Dimiter Ostrev, and Marjan Skrobotˇ University of Luxembourg Interdisciplinary Centre for Security, Reliability and Trust 6, Avenue de la Fonte, L-4364, Esch-sur-Alzette, Luxembourg fjose.becerra, dimiter.ostrev, [email protected] Abstract. Currently, the Simple Password-Based Encrypted Key Ex- change (SPAKE2) protocol of Abdalla and Pointcheval (CT-RSA 2005) is being considered by the IETF for standardization and integration in TLS 1.3. Although it has been proven secure in the Find-then-Guess model of Bellare, Pointcheval and Rogaway (EUROCRYPT 2000), whether it satisfies some notion of forward secrecy remains an open question. In this work, we prove that the SPAKE2 protocol satisfies the so-called weak forward secrecy introduced by Krawczyk (CRYPTO 2005). Further- more, we demonstrate that the incorporation of key-confirmation codes in SPAKE2 results in a protocol that provably satisfies the stronger no- tion of perfect forward secrecy. As forward secrecy is an explicit require- ment for cipher suites supported in the TLS handshake, we believe this work could fill the gap in the literature and facilitate the adoption of SPAKE2 in the recently approved TLS 1.3. Keywords: Provable Security, Password Authenticated Key Exchange, For- ward Secrecy, Common Reference String. 1 Introduction 1.1 SPAKE2 Protocol Password Authenticated Key Exchange (PAKE) protocols allow two users, who only share a password, to agree on a high-entropy session key over a hostile network. The goal is to use the established session key to build a secure channel between the involved parties. The nature of passwords makes PAKEs vulnerable to on-line dictionary attacks, where an adversary tries to impersonate a user by guessing his password, engaging in a protocol execution and verifying if its guess was correct. -
Matrixssl Developer's Guide
MatrixSSL Developer’s Guide MatrixSSL 3.2 Overview 1 Who Is This Document For? 1 Documentation Style Conventions 1 Commercial Version Differences 1 Security Considerations 2 SSL vs. TLS 2 Selecting Cipher Suites 2 Authentication Mode 3 Certificates and Private Keys 4 Application Integration Flow 5 ssl_t Structure 5 Initialization 6 Creating a Session 6 Handshaking 7 Communicating Securely With Peers 9 Ending a Session 11 Closing the Library 11 Configurable Features 12 Functionality Defines 12 PeerSec Networks, Inc. 410 Broadway Ave E. #205 Seattle, WA 98102 T 425.646.7850 F 206.501.4366 [email protected] www.peersec.com Debug Configuration 14 SSL Handshaking 16 Handshake Variations 16 Standard Handshake 16 Client Authentication 17 Session Resumption 18 Re-Handshakes 19 PeerSec Networks, Inc. 410 Broadway Ave E. #205 Seattle, WA 98102 T 425.646.7850 F 206.501.4366 [email protected] www.peersec.com Overview This developer’s guide is a general SSL/TLS overview and a MatrixSSL specific integration reference for adding SSL security into an application. Who Is This Document For? • Software developers that are securing applications with MatrixSSL • Anyone wanting to learn more about MatrixSSL • Anyone wanting to learn more about the SSL/TLS protocol Documentation Style Conventions • File names and directory paths are italicized. • C code literals are distinguished with the Monaco font. Commercial Version Differences Some of the compile options, functions, and structures in this document provide additional features only available in the commercially licensed version of MatrixSSL. Sections of this document that refer to the commercial version will be shaded. MatrixSSL Developer’s Guide © 2002-2011 1/19 Security Considerations Prior to working directly with the MatrixSSL library there are a couple SSL security concepts that application integrators should be familiar with.