Defcon Speaker Discusses Liberating $300K Worth of Bitcoin ...

Hijacking Bitcoin: Routing Attacks on Cryptocurrencies

arXiv:1605.07524
Date: 2017-03-24
Author(s): Maria Apostolaki, Aviv Zohar, Laurent Vanbever

Link to Paper


Abstract
As the most successful cryptocurrency to date, Bitcoin constitutes a target of choice for attackers. While many attack vectors have already been uncovered, one important vector has been left out though: attacking the currency via the Internet routing infrastructure itself. Indeed, by manipulating routing advertisements (BGP hijacks) or by naturally intercepting traffic, Autonomous Systems (ASes) can intercept and manipulate a large fraction of Bitcoin traffic. This paper presents the first taxonomy of routing attacks and their impact on Bitcoin, considering both small-scale attacks, targeting individual nodes, and large-scale attacks, targeting the network as a whole. While challenging, we show that two key properties make routing attacks practical: (i) the efficiency of routing manipulation; and (ii) the significant centralization of Bitcoin in terms of mining and routing. Specifically, we find that any network attacker can hijack few (<100) BGP prefixes to isolate ~50% of the mining power---even when considering that mining pools are heavily multi-homed. We also show that on-path network attackers can considerably slow down block propagation by interfering with few key Bitcoin messages. We demonstrate the feasibility of each attack against the deployed Bitcoin software. We also quantify their effectiveness on the current Bitcoin topology using data collected from a Bitcoin supernode combined with BGP routing data. The potential damage to Bitcoin is worrying. By isolating parts of the network or delaying block propagation, attackers can cause a significant amount of mining power to be wasted, leading to revenue losses and enabling a wide range of exploits such as double spending. To prevent such effects in practice, we provide both short and long-term countermeasures, some of which can be deployed immediately.

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[52] ——, “Massive route leak causes Internet slowdown,” 2015, http://www.bgpmon.net/massive-route-leak-cause-internet-slowdown/.
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submitted by dj-gutz to myrXiv [link] [comments]

'What's wrong with my current cold storage method?' - an examination of potential weaknesses in the most common cold storage methods

Today we are going to discuss cold storage and some specific problems with cold storage. While this applies directly to the Secret Key portion of a key-pair; it also applies to the seed used to back up HD wallets and hardware wallets.
The best way to keep you seed/secret key safe is to have multiple copies in multiple locations perhaps with multiple formats and even better if the keys are split. However not everyone has access to multiple locations, or access to land long term, or more than one place to store their things. This is an examination of faults with individual methods; and not a comprehensive plan, obviously.
Not to say everything is all bad but there are many potential weakness out there, and some in the Bitcoin and crypto community like to know the edge cases of things.
I will also highlight some of the aspects of the Keyois Capsule which is a 'physical bitcoin'.
A physical Bitcoin is a cryptographic key pair, a physical key printed and affixed to what has always been before a coin. The first physical bitcoin coin was the Casascius coin, since then the world of physical bitcoin coins has blossomed as a fun part of the Bitcoin world.
We will focus on mediums relating to cold storage and not ones designed for more everyday use, but this applies to the seed you save to keep your everyday spending wallets safe and backed up.
We will assume you generated your keys securely and that you already have them on some medium. We will also have to ignore endpoint physical security because they can all be carried away the same. Remember your cell phone /hardware wallet/ computer client are only as good as where you put the backup seed phrase, which can be thought of as data much like the SK discussed below.
Written on a piece of paper
Printed on a piece of paper
On laminated paper
Engraved / etched/ ablated/ stamped on a piece of metal
Stored digitally on a computer
Stored digitally on CD, floppy disk, laserdisc, or mini-disc
Stored digitally on a flash drive
Backups are essential for digital data Computer code for performing operations can be corrupted in transfer or in operation. Special systems exist and procedures help data to last longer. For ideas, see this archive.gov page Remember to store in multiple locations. You can lose everything in single structure
A physical bitcoin coin
**What can solve most of these problems? A combination of good backup procedures and encryption. **
If you have permeant access to more than one location (people who live in big cities, without family or cars have a hard time with this) or have people you trust with your money (don't) then look into using some form of Multi-signature option.
The Keyois Capsule is a crypto piggy bank; it can be funded from the outside but you to break it open to get them out. You give me a BIP38 encrypted key pair (well the address not the public key) and I engrave it in this tamper evident and time resistant package. You still have to hold on to the pass phrase that allows you to decrypt it; that is however the same problem as all methods with BIP38 encryption. How to store this without having to trust anyone but still being assured of it's security?
  • Engraving, embossing, or stamping on a sheet of metal is one option; however the metals that are easiest to stamp are ones that melt in a house fire. They could be put in a glass jar that's filled with aerogel and buried. These is the best readily available option for most people but it really can be tedious. - This puts you back at anyone who can see it can steal it so dip in plastic dip, wrap in duct tape, bake in clay, encase in concrete, whatever just don't leave unencrypted keys visible!
  • The cryptosteel is another ready-made option
  • Have the words etched onto glass at home with off the shelf products; but be carful of this idea because the glass can shatter from impact and heat or even sudden temperature changes
  • Anodize the words yourself on a pieces of metal, there used to be a service to help use your home printer to print the words with some chemicals you can buy
  • Bake them in clay, then encase that in epoxy resin so it can't shatter. then paint the outside, in the future you can solvent the paint off and see the written seed
  • Use a combination of techniques to split the seed so that it is safe(because split and separated) and redundant (because backed up).
The most cost effective way for a 'normal' person (without their own land, without more than one location, and who cannot trust anyone else with their funds) to keep their backup seed/ secret key safe from damage from the elements would probably to buy a stamping kit and hammer and some stainless steel sheet or bar, Aluminium can be okay if you have the right alloy but better safe than sorry.
submitted by ProfBitcoin to Bitcoin [link] [comments]

'What is wrong with my current cold storage method' - an examination of potential weaknesses in the most common cold storage methods

Today we are going to discuss cold storage and some specific problems with cold storage. While this applies directly to the Secret Key portion of a key-pair; it also applies to the seed used to back up HD wallets and hardware wallets.
Not to say everything is all bad but there are many potential weakness out there, and some in the Bitcoin and crypto community like to know the edge cases of things.
I will also highlight some of the aspects of the Keyois Capsule which is a 'physical bitcoin'.
A physical Bitcoin is a cryptographic key pair, a physical key printed and affixed to what has always been before a coin. The first physical bitcoin coin was the Casascius coin, since then the world of physical bitcoin coins has blossomed as a fun part of the Bitcoin world.
We will focus on mediums relating to cold storage and not ones designed for more everyday use, but this applies to the seed you save to keep your everyday spending wallets safe and backed up.
We will assume you generated your keys securely and that you already have them on some medium. We will also have to ignore endpoint physical security because they can all be carried away the same. Remember your cell phone /hardware wallet/ computer client are only as good as where you put the backup seed phrase, which can be thought of as data much like the SK discussed below.
Written on a piece of paper
Printed on a piece of paper
On laminated paper
Engraved / etched/ ablated/ stamped on a piece of metal
Stored digitally on a computer
Stored digitally on CD, floppy disk, laserdisc, or mini-disc
Stored digitally on a flash drive
Backups are essential for digital data Computer code for performing operations can be corrupted in transfer or in operation. Special systems exist and procedures help data to last longer. For ideas, see this archive.gov page Remember to store in multiple locations. You can lose everything in single structure
A physical bitcoin coin
What can solve most of these problems? A combination of good backup procedures and encryption.
If you have permeant access to more than one location (people who live in big cities, without family or cars have a hard time with this) or have people you trust with your money (don't) then look into using some form of Multi-signature option.
The Keyois Capsule is a crypto piggy bank; it can be funded from the outside but you to break it open to get them out. You give me a BIP38 encrypted key pair (well the address not the public key) and I engrave it in this tamper evident and time resistant package. You still have to hold on to the pass phrase that allows you to decrypt it; that is however the same problem as all methods with BIP38 encryption. How to store this without having to trust anyone but still being assured of it's security?
  • Engraving, embossing, or stamping on a sheet of metal is one option; however the metals that are easiest to stamp are ones that melt in a house fire. They could be put in a glass jar that's filled with aerogel and buried. These is the best readily available option for most people but it really can be tedious.
  • The cryptosteel is another ready-made option
  • Have the words etched onto glass at home with off the shelf products; but be carful of this idea because the glass can shatter from impact and heat or even sudden temperature changes
  • Anodize the words yourself on a pieces of metal, there used to be a service to help use your home printer to print the words with some chemicals you can buy
  • Bake them in clay, then encase that in epoxy resin so it can't shatter. then paint the outside, in the future you can solvent the paint off and see the written seed
  • Use a combination of techniques to split the seed so that it is safe(because split and separated) and redundant (because backed up).
Characters stamped on Aluminium is probably the most cost effective way to keep a secret key or seed safe from fire and rot.
submitted by ProfBitcoin to btc [link] [comments]

Mossland ICO


About Mossland
Mossland is a AR (augmented reality) gamified platform for owning and trading virtualized real-estate based on mechanics of Monopoly and Pokemon Go.
Virtual assets owned in Mossland can be transferred to other location-based games or services through Moss Chain, the first blockchain for AVR assets.

Next Generation AR
Anything can now be virtualized thanks to a star team of Ex-Samsung and Ex-Google founders.

Moss Coin
Transactions are made with Moss Coin (MOC), a transparent and secured cryptocurrency which will be traded on cryptocurrency exchanges.

Own and Trade Landmarks
You can now own and trade valuable landmarks and real estate around the world in auction houses

Moss Chain
Ownership of assets is secured by Moss Chain, the first AVR assets blockchain.

P2P Advertising
Mossland creates a new advertising platform based on the convergence of real location-based games with AR technology.

Expandable Platform
Virtual assets and their ownership in Mossland could be also transferred to other location based games or services on Moss Chain.
Mossland ICO
Name
Moss Coin
Symbol
MOC
Platform
Ethereum
Total issue
500,000,000 MOC
Price
1 MOC = 0.12 USD
Mossland Team
Founders

Wooram Son
CEO, Co-Founder
3D Computer Graphics ExpertS/W Engineer, Samsung Electronics

Chester Roh
CSO, Co-Founder
Serial EntrepreneurFounder, Inzen (IPO in Korea),Founder, TNC (acquired by Google)Founder, 5Rocks (acquired by Tapjoy)

Minuk Kim
CTO, Co-Founder
3D Computer Graphics ExpertS/W Engineer, Pantech

Yongjun Hong
CFO, Co-Founder
KICPACFO, 5RocksPwC Korea Accountant

Sean Oh
COO, Co-Founder
Digital Human Character ExpertS/W Engineer, Samsung Electronics

Don Lim
VP of Business Development
General Manager, Com2uS USAAdvisory Sales Rep., IBM Korea
ICO Advisors

Louis Jinhwa Kim
Blockchain Advisor
Co-founder, Director, Korea Blockchain AssociationCo-founder, KorbitDirector, Tide InstituteAuthor of World 1st Bitcoin Book, 'Next Money Bitcoin(2013)'

Jason Han
Blockchain Advisor
CEO, KAKAO BlockchainCo-Founder & PartneCTO, FuturePlayFounder & CEO, NexR (acquired by KT)Adjunct Professor, KAIST MBAKAIST PhD in P2P and Distributed System

Jeffrey Lim
Startup Advisor
18+ years of experience in startup ecosystemFormer Head of Campus Seoul, GoogleFormer venture capitalist at Softbank VenturesSerial Entrepreneur

Hash Hao
ICO Advisor
Serial entrepreneur & Fintech expertCo-founder and CMO of INK Labs Foundation7 years experience in Fintech, AI-lending and blockchain

Dennis S. Lee
ICO Advisor
Serial entrepreneurCrypto evangelistInk Labs Foundation Business DeveloperManaging Partner at FutureMoneyFund

Ivan Danishevsky
E-Sports and Gaming Blockchain Advisor
Head of Shoutcasting, Garena.comCCO, Game Show TVFounder, ESM.one - Blockchained EsportsFounder, ESC.watch - Esports Charts

Ilya Mikov
Cryptocurrency Gaming Advisor
Co-Founder, Active GamesFounder, Mobile ActiveSuccessfully raised an ICO round for its mobile MMORPG Lordmancer II.
Product Advisors

Duhee Lee
Startup Advisor
Founder LIKELIONFounder KongdooGoogle Impact Challenge, First Place (People's Choice)Speaker, 66th UN NGO

Vitaly Tkach
Creative Advisor
Creative Director, WargamingFormer Creative Director, Leo Burnett Ukraine

Peter Van Dyke
AR UX & Design Advisor
Interactive UX/Production, AppleCSO & Product Head, GTRProduction Head, npnf KSK PlanetCreative Co-Director, Com2uS Korea

Sunkwan Kim
Art Design Advisor
Creative Leader at Niantic Labs, Google (Ingress, Pokemon GO)Advisor of Weenu, Art up SeoulSenior Visual Designer, Yahoo Korea

Minpyo Hong
Security Advisor
Founder, SEWORKSFounder, SHIFTWORKS (acquired by Infraware)Advised governments on digital security issues for 20+ yearsFive-time consecutive finalist at DEFCON CTF

Yaroslav Kologryvov
Eastern Europe/CIS Market Advisor
Founder, Ukraine's Main University Startup Ecosystem Sikhorsky ChallengeManaging Partner, VANHEALTHING CryptofundFormer CEO, Ukraine's Main Science Park

Baolong Zhang
CG Advisor
Director, DigitallotusLead Character Artist, Supermassive GamesLead Environment Artist, Climax ActionLevel Artist, Ubisoft

Charles Rim
M&A Advisor
General Partner, Access VenturesMD, Tapjoy Korea & SE AsiaVenture Partner, DFJ Athena VCHead of M&A, Google APACCSO, Yahoo Korea & SE Asia

John Chang
Investment Advisor
General Partner, Access VenturesAPAC Head-Equities, Barclays AsiaCEO, Deutsche Bank KoreaCo-Founder, Access Communications

Youngwoon Cha
Graphics & VAR Advisor
CS PhD Candidate, UNC Graphics & Virtual RealityResearcher, KISTResearch Engineer, LG Electronics

John S. Kim
Growth Advisor
CEO & Founder, SendBird (Y Combinator)Director, GREECEO & Founder, Paprika Lab

Tim Chae
Venture Capital Advisor
General Partner, 500 Startups KoreaPartner, 500 StartupsInvestor in 30+ seed stage tech companies in SF/SV and Korea

Changsu Lee
Artificial Intelligence Advisor
Co-Founder & CEO, AllganizeSVP, TapjoyCo-Founder & CEO, 5Rocks

Wonchai Lee
Monetization Advisor
Sr. Football Trader, The Hong Kong Jockey ClubSr. Odds Compiler, Singapore PoolsOddsmaker, SportsToto

Widjaja Tannady
Real Estate Advisor
Founder, Mahanusa CapitalDirector, PT Pacific Place Jakarta
Team Members

Byucryun Choi
Lead Character Artist
Lead Character Artist, NS Studio

Sangmin Lee
Lead Environment Artist
Environment Artist, M Game

Youngdae Cho
Client Engineer
S/W Engineer, NHN NextPMarketer, 5Rocks

Yunu Kim
Server Engineer
S/W Engineer, Line Games

Junchel Park
Blockchain Engineer
S/W Engineer, Kakao

Hyunuk Nam
Blockchain Engineer
S/W Engineer, NHN Next

Seunghyun Kim
Software Engineer
S/W Engineer, NHN Next

Hyunbin Nam
Game Designer
Game Designer, Affinity Game

Jerome Hernandez
Creative Engineer
Creative Engineer, CERN

Emily Park
PR Manager
PR Manager, LineableA.E., Cheil Worldwide
For mor details, please visit to :
web : https://moss.land
White paper :
https://d2vy65gufabiok.cloudfront.net/whitepapeMossland+Whitepaper+-+ENG.pdf
Facebook :
https://www.facebook.com/Mossland-1654411001264423/
Twitter :
https://twitter.com/TheMossland
Mail : [email protected]
Bounty Program :
https://bountyhive.io/join/Mossland
Author : elmisbah
submitted by elmisbah to u/elmisbah [link] [comments]

What is wrong with my current cold storage method?

Today we are going to discuss cold storage and some specific problems with cold storage. While this applies directly to the Secret Key portion of a key-pair; it also applies to the seed used to back up HD wallets and hardware wallets.
The best way to keep you seed/secret key safe is to have multiple copies in multiple locations perhaps with multiple formats and even better if the keys are split. However not everyone has access to multiple locations, or access to land long term, or more than one place to store their things. This is an examination of faults with individual methods; and not a comprehensive plan, obviously.
Not to say everything is all bad but there are many potential weakness out there, and some in the Bitcoin and crypto community like to know the edge cases of things.
I will also highlight some of the aspects of the Keyois Capsule which is a 'physical bitcoin'.
A physical Bitcoin is a cryptographic key pair, a physical key printed and affixed to what has always been before a coin. The first physical bitcoin coin was the Casascius coin, since then the world of physical bitcoin coins has blossomed as a fun part of the Bitcoin world.
We will focus on mediums relating to cold storage and not ones designed for more everyday use, but this applies to the seed you save to keep your everyday spending wallets safe and backed up.
We will assume you generated your keys securely and that you already have them on some medium. We will also have to ignore endpoint physical security because they can all be carried away the same. Remember your cell phone /hardware wallet/ computer client are only as good as where you put the backup seed phrase, which can be thought of as data much like the SK discussed below.
Written on a piece of paper
Printed on a piece of paper
On laminated paper
Engraved / etched/ ablated/ stamped on a piece of metal
Stored digitally on a computer
Stored digitally on CD, floppy disk, laserdisc, or mini-disc
Stored digitally on a flash drive
Backups are essential for digital data Computer code for performing operations can be corrupted in transfer or in operation. Special systems exist and procedures help data to last longer. For ideas, see this archive.gov page Remember to store in multiple locations. You can lose everything in single structure
A physical bitcoin coin
**What can solve most of these problems? A combination of good backup procedures and encryption. **
If you have permeant access to more than one location (people who live in big cities, without family or cars have a hard time with this) or have people you trust with your money (don't) then look into using some form of Multi-signature option.
The Keyois Capsule is a crypto piggy bank; it can be funded from the outside but you to break it open to get them out. You give me a BIP38 encrypted key pair (well the address not the public key) and I engrave it in this tamper evident and time resistant package. You still have to hold on to the pass phrase that allows you to decrypt it; that is however the same problem as all methods with BIP38 encryption. How to store this without having to trust anyone but still being assured of it's security?
  • Engraving, embossing, or stamping on a sheet of metal is one option; however the metals that are easiest to stamp are ones that melt in a house fire. They could be put in a glass jar that's filled with aerogel and buried. These is the best readily available option for most people but it really can be tedious. - This puts you back at anyone who can see it can steal it so dip in plastic dip, wrap in duct tape, bake in clay, encase in concrete, whatever just don't leave unencrypted keys visible!
  • The cryptosteel is another ready-made option
  • Have the words etched onto glass at home with off the shelf products; but be carful of this idea because the glass can shatter from impact and heat or even sudden temperature changes
  • Anodize the words yourself on a pieces of metal, there used to be a service to help use your home printer to print the words with some chemicals you can buy
  • Bake them in clay, then encase that in epoxy resin so it can't shatter. then paint the outside, in the future you can solvent the paint off and see the written seed
  • Use a combination of techniques to split the seed so that it is safe(because split and separated) and redundant (because backed up).
The most cost effective way for a 'normal' person (without their own land, without more than one location, and who cannot trust anyone else with their funds) to keep their backup seed/ secret key safe from damage from the elements would probably to buy a stamping kit and hammer and some stainless steel sheet or bar, Aluminium can be okay if you have the right alloy but better safe than sorry.
submitted by ProfBitcoin to Keyois [link] [comments]

http://blog.btcgermany.eu/korean-bitcoin-startup-devign-lab-nets-200k-from-k-cube-ventures/

[SEOUL, Oct. 7, 2014] Devign Lab (CEO: Myung Hun Cha) has announced today that the company has raised about $200K from K Cube Ventures (CEO: Jimmy Rim). Devign Lab devised a bitcoin market ‘Coinone (link: coinone.co.kr). Coinone enables an amateur to professionals to transact bitcoin easily through a tailored UI(User Interface) with 0% of transaction fee.[image] coinone loge 1Coinone’s specialty compared to existing services comes from its professional transaction system. With the fluctuation of bitcoin prices, needs for expertised UI have been constantly growing. To satisfy these demands, Coinone implemented the first web-based HTS in South Korea. HTS was designed to provide an up to date bidding/contract information for users who want to purchase bitcoin conveniently. Plus, Coinone could be utilized in any kind of OS (Windows, Android and iOS) through multi- platforms regardless of mobile device resolutions. Those features could be found in Coinone only.Devign Lab’s next step is to stabilize and develop its system. Moreover, Devign Lab is planning to launch one click payment service ‘Coinpay’, a one click payment service which enables users to transact with one simple click. Moreover, Devign Lab will release its own application to use ‘Coinpay’ for users’convenience.Devign Lab is planning an interesting projects as well. One of the projects is electronic contract solution ‘Smart Contract’, aiming to provide an advanced level of security and to reduce the burden of transaction cost.Devign Lab’s employees consists of POSTECH (Top 9 Asian University) Computer Science graduates with IT competition awards and Myung Hun Cha, who was awarded 3rd place in the world’s largest hacking competition Defcon as a CEO. Devign Lab has produced the most advanced security system with the aid of security specialists in the IT industry and protect customer’s valued assets securely.
submitted by coinclip to Bitcoin [link] [comments]

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Bitcoin Whale Wallets With 1000+ BTC Or More Spike To ...

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