AUTOCRYPT: Enabling Homomorphic Computation on Servers to Protect Sensitive Web Content
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A History of End-To-End Encryption and the Death of PGP
25/05/2020 A history of end-to-end encryption and the death of PGP Hey! I'm David, a security engineer at the Blockchain team of Facebook (https://facebook.com/), previously a security consultant for the Cryptography Services of NCC Group (https://www.nccgroup.com). I'm also the author of the Real World Cryptography book (https://www.manning.com/books/real-world- cryptography?a_aid=Realworldcrypto&a_bid=ad500e09). This is my blog about cryptography and security and other related topics that I Ûnd interesting. A history of end-to-end encryption and If you don't know where to start, you might want to check these popular the death of PGP articles: posted January 2020 - How did length extension attacks made it 1981 - RFC 788 - Simple Mail Transfer Protocol into SHA-2? (/article/417/how-did-length- extension-attacks-made-it-into-sha-2/) (https://tools.ietf.org/html/rfc788) (SMTP) is published, - Speed and Cryptography the standard for email is born. (/article/468/speed-and-cryptography/) - What is the BLS signature scheme? (/article/472/what-is-the-bls-signature- This is were everything starts, we now have an open peer-to-peer scheme/) protocol that everyone on the internet can use to communicate. - Zero'ing memory, compiler optimizations and memset_s (/article/419/zeroing-memory- compiler-optimizations-and-memset_s/) 1991 - The 9 Lives of Bleichenbacher's CAT: New Cache ATtacks on TLS Implementations The US government introduces the 1991 Senate Bill 266, (/article/461/the-9-lives-of-bleichenbachers- which attempts to allow "the Government to obtain the cat-new-cache-attacks-on-tls- plain text contents of voice, data, and other implementations/) - How to Backdoor Di¸e-Hellman: quick communications when appropriately authorized by law" explanation (/article/360/how-to-backdoor- from "providers of electronic communications services di¸e-hellman-quick-explanation/) and manufacturers of electronic communications - Tamarin Prover Introduction (/article/404/tamarin-prover-introduction/) service equipment". -
Detecting and Preventing Active Attacks Against Autocrypt Release 0.10.0
Detecting and preventing active attacks against Autocrypt Release 0.10.0 NEXTLEAP researchers Jan 09, 2020 Contents 1 Introduction2 1.1 Attack model and terminology............................2 1.2 Problems of current key-verification techniques...................3 1.3 Integrating key verification with general workflows.................3 1.4 Supplementary key consistency through ClaimChains................4 1.5 Detecting inconsistencies through Gossip and DKIM................5 2 Securing communications against network adversaries6 2.1 Setup Contact protocol................................7 2.2 Verified Group protocol................................ 12 2.3 History-verification protocol............................. 17 2.4 Verifying keys through onion-queries......................... 20 3 Key consistency with ClaimChains 23 3.1 High level overview of the ClaimChain design.................... 23 3.2 Use and architecture................................. 24 3.3 Evaluating ClaimChains to guide verification.................... 26 4 Using Autocrypt key gossip to guide key verification 28 4.1 Attack Scenarios................................... 28 4.2 Probability of detecting an attack through out of band verification......... 29 5 Using DKIM signature checks to guide key verification 32 5.1 DKIM Signatures on Autocrypt Headers....................... 32 5.2 Device loss and MITM attacks............................ 33 5.3 Open Questions.................................... 34 1 1 Introduction This document considers how to secure Autocrypt1-capable mail apps against active network at- tackers. Autocrypt aims to achieve convenient end-to-end encryption of e-mail. The Level 1 Autocrypt specification offers users opt-in e-mail encryption, but only considers passive adver- saries. Active network adversaries, who could, for example, tamper with the Autocrypt header during e-mail message transport, are not considered in the Level 1 specification. Yet, such active attackers might undermine the security of Autocrypt. -
Request for Reconsideration After Final Action
Under the Paperwork Reduction Act of 1995 no persons are required to respond to a collection of information unless it displays a valid OMB control number. PTO Form 1960 (Rev 10/2011) OMB No. 0651-0050 (Exp 09/20/2020) Request for Reconsideration after Final Action The table below presents the data as entered. Input Field Entered SERIAL NUMBER 87031396 LAW OFFICE ASSIGNED LAW OFFICE 116 MARK SECTION MARK https://tmng-al.uspto.gov/resting2/api/img/87031396/large LITERAL ELEMENT CRYPTTALK STANDARD CHARACTERS YES USPTO-GENERATED IMAGE YES MARK STATEMENT The mark consists of standard characters, without claim to any particular font style, size or color. ARGUMENT(S) In the Official Action, the Examiner has made final the refusal to register the "CRYPTTALK" mark on the Principal Register because of the "likelihood of confusion" of the mark with prior registered marks. Applicant respectfully disagrees and believes that the Examiner has failed to make a prima facie showing of likelihood of confusion. I. NO LIKELIHOOD OF CONFUSION WITH U.S. REGISTRATION NOS. 4,707,027 and 4,859,726 A. The term "CRYPT" is Not a Distinctive Mark. The Examiner does not discuss the possibility of the cited registrations being viewed by the relevant consumer as the term "CRIP" and instead suggests that the terms "CRYPT" and "CRIPT" are the only relevant words to compare. The Examiner goes on to conclude that "CRYPT" and "CRIPT" in the respective marks "appear similar and are phonetic equivalents." This alleged similarity has been made the basis of the Examiners refusal to register Applicant's mark. -
Easy Encryption for Email, Photo, and Other Cloud Services John Seunghyun Koh
Easy Encryption for Email, Photo, and Other Cloud Services John Seunghyun Koh Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy under the Executive Committee of the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2021 © 2021 John Seunghyun Koh All Rights Reserved Abstract Easy Encryption for Email, Photo, and Other Cloud Services John Seunghyun Koh Modern users carry mobile devices with them at nearly all times, and this likely has contribut- ed to the rapid growth of private user data—such as emails, photos, and more—stored online in the cloud. Unfortunately, the security of many cloud services for user data is lacking, and the vast amount of user data stored in the cloud is an attractive target for adversaries. Even a single compro- mise of a user’s account yields all its data to attackers. A breach of an unencrypted email account gives the attacker full access to years, even decades, of emails. Ideally, users would encrypt their data to prevent this. However, encrypting data at rest has long been considered too difficult for users, even technical ones, mainly due to the confusing nature of managing cryptographic keys. My thesis is that strong security can be made easy to use through client-side encryption using self-generated per-device cryptographic keys, such that user data in cloud services is well pro- tected, encryption is transparent and largely unnoticeable to users even on multiple devices, and encryption can be used with existing services without any server-side modifications. This dis- sertation introduces a new paradigm for usable cryptographic key management, Per-Device Keys (PDK), and explores how self-generated keys unique to every device can enable new client-side encryption schemes that are compatible with existing online services yet are transparent to users. -
Smarx OS Compendium 2020 for the CRYPTO-BOX
2020 EDITION Smarx® Compendium d s p . ) r e v o C _ n a M x r a m S ( a s 2 1 v o N 7 2 - www.marx.com 0 2 We highly appreciate and value your comments and suggestions! Suggestions for improvements will be honored with: • Free Business Support for 6 months • Enrollment in our BE !" ester program Software security is a growing challenge and requires constant improving " be part of the process! $lease send sugestions and error report to: • $$%& software/hardware in general and documentation (including this Compendium*: support@mar,.com • WEB and online ordering system related: webmaster+mar,.com Smar, .S )ompendium November 2020 )opyright 1 2002, 2020 2!345 )ryptoTech 6$ 7 Table of Contents 8. What is this Compendium !bout?--------------------------------------------------------------------------------: 8-8. ;ntroduction--------------------------------------------------------------------------------------------------------: 8.2. What is /ew9-------------------------------------------------------------------------------------------------------: 8-7. What to Find Where in this )ompendium--------------------------------------------------------------< 8-=. $rofessional Software $rotection Secures 3evenue----------------------------------------------< 8->. he )3?$ ."BO45@ardware-----------------------------------------------------------------------------88 8->-8. )3?$ ."BOX 2odels--------------------------------------------------------------------------------88 8->.2. echnical Features of the )3?$ ."BO45----------------------------------------------------88 -
Easy Email Encryption with Easy Key Management
Why Joanie Can Encrypt: Easy Email Encryption with Easy Key Management John S. Koh Steven M. Bellovin Jason Nieh Columbia University Columbia University Columbia University New York, NY New York, NY New York, NY koh@cs:columbia:edu smb@cs:columbia:edu nieh@cs:columbia:edu Abstract subjected to a simple password recovery and reset attack Email privacy is of crucial importance. Existing email encryp- which granted the attacker full access to her personal email tion approaches are comprehensive but seldom used due to account on the Yahoo! Mail website. John Brennan’s AOL their complexity and inconvenience. We take a new approach web email account was compromised via social engineering. to simplify email encryption and improve its usability by im- Adversaries also sometimes seize entire email servers such plementing receiver-controlled encryption: newly received as in the cases of cock.li and TorMail [30, 41], or compromise messages are transparently downloaded and encrypted to a them, such as in the Sony Pictures email leaks [43]. locally-generated key; the original message is then replaced. The common thread is that a compromise exposes the To avoid the problem of moving a single private key between entire history of affected users’ emails after a single breach. devices, we implement per-device key pairs: only public keys With the explosive growth in cloud storage, it is easy to need be synchronized via a simple verification step. Com- keep gigabytes of old emails at no cost. Gmail’s massive promising an email account or server only provides access storage capacity—up to 15 GB for free, or 30 TB for paid to encrypted emails. -
Pentest-Report Thunderbird & RNP (MOSS)
Dr.-Ing. Mario Heiderich, Cure53 Bielefelder Str. 14 D 10709 Berlin cure53.de · [email protected] Audit-Report RNP & Thunderbird Integration 08.2020 Cure53, Dr.-Ing. M. Heiderich, M. Wege, BSc. J. Hector, MSc. D. Weißer, MSc. R. Peraglie, Dr. N. Kobeissi Index Introduction Scope Identified Vulnerabilities RNP-01-001 WP1: Integer overflow due to expiration time of PGP v3 keys (Low) RNP-01-004 WP1: Potential Integer underflow in partial_dst_write() (Low) RNP-01-005 WP1: Literal packet parsing allows for Integer underflow (Low) RNP-01-006 WP2: Evaluation of password strength insufficient (Low) RNP-01-007 WP1: encrypt_secret_key() does not wipe keybuf from memory (Low) RNP-01-012 WP1: Logic issue potentially leaves key material unlocked (Medium) RNP-01-014 WP1: Key manipulation via uncertified Auto-Import (Medium) Miscellaneous Issues RNP-01-002 WP3: Automatic handling of autocrypt-gossip header (Info) RNP-01-003 WP3: Possible race condition when reading from disk (Info) RNP-01-008 WP3: Partially unencrypted email insufficiently detected (Low) RNP-01-009 WP1: mem_dest_own_memory() callers do not check for NULL (Info) RNP-01-010 WP1: Outdated and vulnerable Botan library version (Info) RNP-01-011 WP1: Potential overflow in librepgp due to invalid size check (Low) RNP-01-013 WP2: Forbidden cipher-suites/algorithms recommendations (Info) Conclusions Cure53, Berlin · 06/07/21 1/26 Dr.-Ing. Mario Heiderich, Cure53 Bielefelder Str. 14 D 10709 Berlin cure53.de · [email protected] Introduction “RNP is a set of OpenPGP (RFC4880) tools that works on Linux, *BSD and macOS as a replacement of GnuPG. It is maintained by Ribose after being forked from NetPGP, itself originally written for NetBSD.” From https://www.rnpgp.com/software/rnp/ This report documents the results of a large-scale assessment of the RNP C++ OpenPGP implementation and its integration with the Thunderbird email client. -
Standardising by Running Code'': the Signal Protocol and De Facto
“Standardising by running code”: the Signal protocol and de facto standardisation in end-to-end encrypted messaging Ksenia Ermoshina, Francesca Musiani To cite this version: Ksenia Ermoshina, Francesca Musiani. “Standardising by running code”: the Signal protocol and de facto standardisation in end-to-end encrypted messaging. Internet histories, Taylor & Francis, 2019, pp.1-21. 10.1080/24701475.2019.1654697. halshs-02319701 HAL Id: halshs-02319701 https://halshs.archives-ouvertes.fr/halshs-02319701 Submitted on 18 Oct 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. “Standardizing by running code”: The Signal protocol and de facto standardization in end-to-end encrypted messaging Ksenia Ermoshina Francesca Musiani Center for Internet and Society, CNRS, Paris, France Centre Internet et Société (CIS-CNRS), 59-61 rue Pouchet, 75849 Paris cedex 17 Corresponding author email: [email protected] Ksenia Ermoshina (PhD, MINES ParisTech) is a postdoctoral researcher at the Center for Internet and Society (CIS) of the French National Centre for Scientific Research (CNRS), and is an Associate Researcher at the Citizen Lab, Munk School of Global Affairs, University of Toronto. Her research focuses on information operations within the Russian-Ukrainian armed conflict, including digital threats to journalists and civil society organizations, Internet censorship, and surveillance. -
Keamanan Komputer
Nama : Hartono Npm : 13411251 Kelas : 4ib03 Tugas : KEAMANAN KOMPUTER Keamanan komputer atau dalam Bahasa Inggris computer security atau dikenal juga dengan sebutan cybersecurity atau IT security adalah keamanan infromasi yang diaplikasikan kepada komputer dan jaringannya. Computer security atau keamanan komputer bertujuan membantu user agar dapat mencegah penipuan atau mendeteksi adanya usaha penipuan di sebuah sistem yang berbasis informasi. Informasinya sendiri memiliki arti non fisik. Keamanan komputer adalah suatu cabang teknologi yang dikenal dengan nama keamanan informasi yang diterapkan pada komputer. Sasaran keamanan komputer antara lain adalah sebagai perlindungan informasi terhadap pencurian atau korupsi, atau pemeliharaan ketersediaan, seperti dijabarkan dalam kebijakan keamanan. Sistem keamanan komputer merupakan sebuah upaya yang dilakukan untuk mengamankan kinerja dan proses komputer. Penerapan computer security dalam kehidupan sehari-hari berguna sebagai penjaga sumber daya sistem agar tidak digunakan, modifikasi, interupsi, dan diganggu oleh orang yang tidak berwenang. Keamanan bisa diindentifikasikan dalam masalah teknis, manajerial, legalitas, dan politis. computer security akan membahas 2 hal penting yaitu Ancaman/Threats dan Kelemahan sistem/vulnerabillity. Keamanan komputer memberikan persyaratan terhadap komputer yang berbeda dari kebanyakan persyaratan sistem karena sering kali berbentuk pembatasan terhadap apa yang tidak boleh dilakukan komputer. Ini membuat keamanan komputer menjadi lebih menantang karena sudah -
Autocrypt Documentation Release 0.5
Autocrypt Documentation Release 0.5 hpk, dkg etc.al Apr 11, 2017 Contents 1 Introducing Autocrypt: E-Mail Encryption for Everyone3 1.1 The social Autocrypt approach......................................3 1.2 The technical Autocrypt approach....................................3 2 Autocrypt features 5 3 Channels 7 4 Upcoming events 9 5 Example Data Flows and State Transitions 11 5.1 Basic network protocol flow....................................... 12 5.2 “Happy path” example: 1:1 communication............................... 12 5.3 Group mail communication (1:N).................................... 12 5.4 Losing access to decryption key..................................... 13 5.5 Downgrading / switch to a MUA without Autocrypt support...................... 13 6 Guidance for Implementers of Autocrypt Level 0 15 6.1 Requirements on MUA/E-mail Provider interactions.......................... 16 6.2 Secret key generation and storage.................................... 16 6.3 Claiming the Account.......................................... 16 6.4 Header injection in outbound mail.................................... 17 6.5 Deriving a Parsed Autocrypt Header from a Message.......................... 17 6.6 Internal state storage........................................... 18 6.7 Updating internal state upon message receipt.............................. 19 6.8 Provide a recommendation for message encryption........................... 20 6.9 Encrypt outbound mail as requested................................... 22 6.10 Specific User Interface Elements.................................... -
Verifying Constant-Time Implementations
Verifying Constant-Time Implementations José Bacelar Almeida, HASLab/INESC TEC and University of Minho; Manuel Barbosa, HASLab/INESC TEC and DCC FCUP; Gilles Barthe and François Dupressoir, IMDEA Software Institute; Michael Emmi, Bell Labs and Nokia https://www.usenix.org/conference/usenixsecurity16/technical-sessions/presentation/almeida This paper is included in the Proceedings of the 25th USENIX Security Symposium August 10–12, 2016 • Austin, TX ISBN 978-1-931971-32-4 Open access to the Proceedings of the 25th USENIX Security Symposium is sponsored by USENIX Verifying Constant-Time Implementations José Bacelar Almeida Manuel Barbosa HASLab - INESC TEC & Univ. Minho HASLab - INESC TEC & DCC FCUP Gilles Barthe François Dupressoir Michael Emmi IMDEA Software Institute IMDEA Software Institute Bell Labs, Nokia Abstract in the execution platform [23] or by interacting remotely The constant-time programming discipline is an effective with the implementation through a network. Notable ex- countermeasure against timing attacks, which can lead to amples of the latter include Brumley and Boneh’s key complete breaks of otherwise secure systems. However, recovery attacks against OpenSSL’s implementation of adhering to constant-time programming is hard on its the RSA decryption operation [15]; and the Canvel et own, and extremely hard under additional efficiency and al. [16] and Lucky 13 [4] timing-based padding-oracle legacy constraints. This makes automated verification of attacks, that recover application data from SSL/TLS con- constant-time code an essential component for building nections [38]. A different class of timing attacks exploit secure software. side-effects of cache-collisions; here the attacker infers We propose a novel approach for verifying constant- memory-access patterns of the target program — which time security of real-world code. -
Sok: Securing Email—A Stakeholder-Based Analysis
SoK: Securing Email—A Stakeholder-Based Analysis Jeremy Clark1, Paul C. van Oorschot2, Scott Ruoti3, Kent Seamons4, and Daniel Zappala4 1 Concordia University, Canada [email protected] 2 Carleton University, Canada [email protected] 3 University of Tennessee [email protected] 4 Brigham Young University [email protected] [email protected] Abstract. While email is the most ubiquitous and interoperable form of online communication today, it was not conceived with strong security guarantees, and the ensuing security enhancements are, by contrast, lacking in both ubiquity and interoperability. This situation motivates our research. We begin by identifying a variety of stakeholders who have an interest in the current email system and in efforts to provide secure solutions. We then use the tussle among stakeholders to explain the evolution of fragmented secure email solutions undertaken by industry, academia, and independent developers, and to draw the conclusion that a one-size- fits-all solution is unlikely. We highlight that vulnerable users are not well served by current solutions. We also account for the failure of PGP, and argue secure messaging, well complimentary, is not a fully substitutable technology. 1 Introduction Email has been called “probably the most valuable service on the Internet” [14]. It has evolved over its 50-year history to become a pillar of seamless interoperability—if you know someone’s email address, you can send email to them [111] across a diverse range of desktop, mobile, and web client software. As an indication of its near-universal acceptance, an email address is often required to create online accounts and to make online purchases.