On the Effective Prevention of TLS Man-In-The- Middle Attacks in Web
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Browser Security Information
Browser Security Information Customer security is important to us. Our top priority is to protect the privacy of your personal account information and your financial transactions FirstLine Mortgages is leading the way in Internet banking services and uses several layers of robust security technology to help ensure the confidentiality of transactions across the Internet. The first security level begins with your Web browser. When you access FirstLine Mortgages Internet Site , your browser is checked to ensure that it meets our minimum requirements. Additionally, we only allow customers with browsers that use 128-bit encryption (one of the highest levels of browser security available today) to bank on our web site. But, even with this validation, there are other precautions you should follow to maximize your protection. You have a responsibility to ensure your own security. The browser validation will verify the browser type you are using, your browser encryption level, the version of Netscape or Microsoft browser, as well as Javascript and cookies being enabled. To access -FirstLine Mortgages Internet site , you need to use: • a Netscape browser version 4.06 or better with a minimum 128-bit encryption technology • a Microsoft browser version 4.01 SP2 or better with a minimum 128-bit encryption technology • Javascript (please see below for more information about how to check and enable Javascript support) • Cookies (see below) If your browser does not meet all of these requirements, you will need to upgrade your browser to access the FirstLine Internet Site . To upgrade your browser, select the Netscape or Microsoft button below and download the latest browser version. -
But Were Afraid to Ask!)
05_576593 ch01.qxd 10/12/04 9:55 PM Page 9 Chapter 1 All You Ever Wanted to Know about JavaScript (But Were Afraid to Ask!) In This Chapter ᮣ Understanding a working definition of JavaScript ᮣ Dispelling common JavaScript misconceptions ᮣ Getting started with JavaScript tools ᮣ Finding information online aybe you’ve surfed to a Web site that incorporates really cool features, Msuch as ߜ Images that change when you move your mouse over them ߜ Slideshow animations ߜ Input forms with pop-up messages that help you fill in fields correctly ߜ Customized messages that welcome repeat visitors By using JavaScript and the book you’re reading right now you can create all these effects and many more! The Web page in Figure 1-1 shows you an example COPYRIGHTEDof the kinds of things that you canMATERIAL look forward to creating for your own site. A lot has changed since the previous edition of JavaScript For Dummies came out. Perhaps the biggest change is the evolution of DHTML, or dynamic HTML. DHTML refers to JavaScript combined with HTML and cascading style sheets, and it’s a powerful combination you can use to create even more breathtak- ingly cool Web sites than ever before. 05_576593 ch01.qxd 10/12/04 9:55 PM Page 10 10 Part I: Building Killer Web Pages for Fun and Profit Figure 1-1: JavaScript lets you add interactive features to your Web site quickly and easily. Along with this increased power comes increased complexity, unfortunately — but that’s where this new, improved, better-tasting edition of JavaScript For Dummies comes in! Even if you’re not a crackerjack programmer, you can use the techniques and sample scripts in this book to create interactive Web pages bursting with animated effects. -
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. -
Javascript Security
Color profile: Generic CMYK printer profile Composite Default screen Complete Reference / JavaScript: TCR / Powell & Schneider / 225357-6 / Chapter 22 Blind Folio 679 22 JavaScript Security ownloading and running programs written by unknown parties is a dangerous proposition. A program available on the Web could work as advertised, but then Dagain it could also install spyware, a backdoor into your system, or a virus, or exhibit even worse behavior such as stealing or deleting your data. The decision to take the risk of running executable programs is typically explicit; you have to download the program and assert your desire to run it by confirming a dialog box or double-clicking the program’s icon. But most people don’t think about the fact that nearly every time they load a Web page, they’re doing something very similar: inviting code—in this case, JavaScript—written by an unknown party to execute on their computer. Since it would be phenomenally annoying to have to confirm your wish to run JavaScript each time you loaded a new Web page, the browser implements a security policy designed to reduce the risk such code poses to you. A security policy is simply a set of rules governing what scripts can do, and under what circumstances. For example, it seems reasonable to expect browsers’ security policies to prohibit JavaScript included on Web pages downloaded from the Internet from having access to the files on your computer. If they didn’t, any Web page you visited could steal or destroy all of your files! In this chapter we examine the security policies browsers enforce on JavaScript embedded in Web pages. -
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 -
SSL Checklist for Pentesters
SSL Checklist for Pentesters Jerome Smith BSides MCR, 27th June 2014 # whoami whoami jerome • Pentester • Author/trainer – Hands-on technical – Web application, infrastructure, wireless security • Security projects – Log correlation – Dirty data – Incident response exercises • Sysadmin • MSc Computing Science (Dist) • www.exploresecurity.com | @exploresecurity Introduction • Broad review of SSL/TLS checks – Viewpoint of pentester – Pitfalls – Manually replicating what tools do (unless you told the client that SSL Labs would be testing them ) – Issues to consider reporting (but views are my own) • While SSL issues are generally low in priority, it’s nice to get them right! • I’m not a cryptographer: this is all best efforts SSLv2 • Flawed, e.g. no handshake protection → MITM downgrade • Modern browsers do not support SSLv2 anyway – Except for IE but it’s disabled by default from IE7 – That mitigates the risk these days – http://en.wikipedia.org/wiki/Transport_Layer_Security#W eb_browsers • OpenSSL 1.0.0+ doesn’t support it – Which means SSLscan won’t find it – General point: tools that dynamically link to an underlying SSL library in the OS can be limited by what that library supports SSLv2 • Same scan on different OpenSSL versions: SSLv2 • testssl.sh warns you – It can work with any installed OpenSSL version • OpenSSL <1.0.0 s_client -ssl2 switch – More on this later • Recompile OpenSSL – http://blog.opensecurityresearch.com/2013/05/fixing-sslv2-support- in-kali-linux.html • SSLyze 0.7+ is statically linked – Watch out for bug https://github.com/iSECPartners/sslyze/issues/73 -
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 -
Guideline for Securing Your Web Browser P a G E | 2
CMSGu2011-02 CERT-MU SECURITY GUIDELINE 2011 - 02 Mauritian Computer Emergency Response Team Enhancing Cyber Security in Mauritius Guideline For Securing Your Web Browser National Computer Board Mauritius JuJunene 2011 2011 Version 1.7 IssueIssue No. No. 4 2 National Computer Board © Table of Contents 1.0 Introduction .......................................................................................................................... 7 1.1 Purpose and Scope ........................................................................................................... 7 1.2 Audience........................................................................................................................... 7 1.3 Document Structure.......................................................................................................... 7 2.0 Background .......................................................................................................................... 8 3.0 Types of Web Browsers ....................................................................................................... 9 3.1 Microsoft Internet Explorer .............................................................................................. 9 3.2 Mozilla Firefox ................................................................................................................. 9 3.3 Safari ................................................................................................................................ 9 3.4 Chrome .......................................................................................................................... -
Browser Security
Transcript of Episode #38 Browser Security Description: Steve and Leo discuss the broad topic of web browser security. They examine the implications of running "client-side" code in the form of interpreted scripting languages such as Java, JavaScript, and VBScript, and also the native object code contained within browser "plug- ins" including Microsoft’s ActiveX. Steve outlines the "zone-based" security model used by IE and explains how he surfs with high security under IE, only "lowering his shields" to a website after he’s had the chance to look around and decide that the site is trustworthy. High quality (64 kbps) mp3 audio file URL: http://media.GRC.com/sn/SN-038.mp3 Quarter size (16 kbps) mp3 audio file URL: http://media.GRC.com/sn/sn-038-lq.mp3 Leo Laporte: Bandwidth for Security Now! is provided by AOL Radio at AOL.com/podcasting. This is Security Now! with Steve Gibson, Episode 38 for May 4, 2006: Browser Security. Security Now! is brought to you by Astaro, makers of the Astaro Security Gateway, on the web at www.astaro.com. So finally the sun is shining in beautiful California. We have summer, or at least spring finally arrived. And, look, Steve Gibson’s wearing a tank top and shorts. No, he’s not. Steve Gibson: Well, it’s dry in Toronto, Leo. You were all chapped; I was all, like, chapped just after one day. Leo: I am. And, you know, they complain in Toronto that it’s too humid because they have the lake effect. But I guess it gets humid some other time because I – chapped is the word, exactly. -
New Standards and Upcoming Technologies in Browser Security
OWASP The OWASP Foundation AppSec Europe 2011 http://www.owasp.org New Standards and upcoming Technologies in Browser Security Tobias Gondrom Board member of OWASP London Chair of IETF Web Security WG [email protected] Copyright © The OWASP Foundation Permission is granted to copy, distribute and/or modify this document under the terms of the OWASP License. Tobias Gondrom • 12 years information security experience • 10 years application development experience • Information Security & Risk Management, Research and Advisory, Director • Author of Standards on Digital Signatures and Secure Archiving • Chair of IETF Web Security Working Group http://datatracker.ietf.org/wg/websec/charter/ Member of the IETF Security Directorate • London OWASP chapter board member (former OWASP Germany chapter lead) www.owasp.org Browser Security • History • What’s the problem • Who & Why • What’s been done • When 3 Browser Security • History • What’s the problem • Who & Why • What’s been done • When 4 History • Internet/Arpanet Protocols were designed for robustness and exchanging information and cross reference of content… …. but not with security and active content in mind • We try to fix Application Security on the Application end ever since 5 Browser Security • History • What’s the problem • Who & Why • What’s been done • When 6 What’s the problem - OWASP Top 10 What’s the problem - OWASP Top 10 What’s the problem - No Clear separation between content and executed code - Relies on trust relationships (trust on first use / trusted source) - Weak channel protection - Authentication & leakage of credentials => Today, Web Applications try to fix this on the Application level with little support of the underlying infrastructure 9 What’s the problem Client Server Inform & Influence Security Posture 10 Think Big - What if we can…. -
Browser Security Guidance: Mozilla Firefox
GOV.UK Guidance Browser Security Guidance: Mozilla Firefox Published Contents 1. Usage scenario 2. Summary of browser security 3. How the browser can best satisfy the security recommendations 4. Network architecture 5. Deployment process 6. Recommended configuration 7. Enterprise considerations This ALPHA guidance builds on the End User Devices Platform Security Guidance and is applicable to devices running Mozilla Firefox on a supported and well configured version of Windows. This guidance was tested on 64bit Windows 8.1 Enterprise edition running Firefox 31.1.1 ESR. 1. Usage scenario Firefox will be used to access a variety of web services including: accessing intranet services hosted on an enterpriseprovided OFFICIAL network accessing enterprise cloud services sourced from the Digital Marketplace accessing other Internet services and web resources To support these scenarios, the following architectural choices are recommended: All data should be routed through a secure enterprise VPN to ensure the confidentiality and integrity of traffic intended for the enterprise intranet All Internet data should be routed through an enterprisehosted proxy to benefit from enterprise protective monitoring and logging solutions Arbitrary thirdparty extension installation by users is not permitted in the browser. A list of allowed trusted apps and extensions can be configured in Group Policy 2. Summary of browser security This browser has been assessed against each of the 12 security recommendations, and that assessment is shown in the table below. Explanatory text indicates that there is something related to that recommendation that the risk owners should be aware of. Rows marked [!] represent a more significant risk. -
Browser Security Issues and Solutions
Browser security issues and solutions HORNYÁK ZSOLT A BIZTONSÁGOS ELEKTRONIKUS KERESKEDELEM ALAPJAI (BMEVIHIM219) Outline • Why Are Browsers Attack Targets? • Security in Google Chrome • Security in Chromium • Malicious Extensions • Cookie stealing • Vulnerabilities Resulting From the Use of HTML and JavaScript • Vulnerabilities in SSL/TLS • ZIP Bombs, XML Bombs, XML eXternal Entities Why Are Browsers Attack Targets? The web browser is our window to the world. We use it every day for tasks including: • Mail • Shopping • Social Networking • Finance Management • Business The browser has access to personal information as plaintext, so it’s inevitable that it gets attacked. Security in Google Chrome Try to minimize the damage • Every sufficiently big software contains bugs • Mozilla Firefox’s source code has approximately 3.7 million lines • Let’s try to minimize the… • Severity of vulnerabilities • Window of vulnerabilities • Frequency of exposure Reducing the severity of vulnerabilities • Web content is run within a JavaScript Virtual Machine, to protect the web sites from each other • Exploit mitigation • ASLR (Address Space Layout Randomization) • Randomizing the mapping location of key system components • DEP (Data Execution Prevention) • Marking memory pages as non-executable • SafeSEH (Safe exception handlers) • Heap Corruption Detection • Stack Overrun Detection using canaries • Using an OS-level sandbox Chrome’s architecture Charles Reis, Google; Adam Barth, UC Berkeley ; Carlos Pizano, Google: Browser Security: Lessons from Google