devcon 4 / blockchain autopsies analyzing selfdestructs
- YouTube
- IPFS
- Details
Blockchain Autopsies - Analyzing selfdestructs
Duration: 00:06:21
Speaker: Jay Little
Type: Talk
Expertise: Intermediate
Event: Devcon
Date: Invalid Date
On the blockchain, contracts may be lost but are never forgotten. Of the over 1,800,000 Ethereum smart contracts ever created, more than 54,000 are empty. When a contract’s purpose is fulfilled, the owner typically triggers a self-destruct switch that removes code and state. These steps are similar to what an attacker would do after hijacking a contract. Is it likely the selfdestruct was intentional or performed by a trusted third party? Or was it a hack or fraud? Old contracts have been purged from the world computer’s working memory but they can be reconstructed and analyzed. By investigating the transactions leading up to the selfdestruct, the circumstances of contract deaths can be determined.
Categories
- Related
Devcon
Talk
17:48
Ethereum Security
Martin Swende gives their talk on Ethereum Security.
Devcon
Talk
19:41
Evolution of Smart Contract Security in the Ethereum Ecosystem
A lot has changed in the smart contract development ecosystem in the year since DEVCON2. Our perspective as leaders of the smart contract security community OpenZeppelin shows us that the industry is maturing. We give a brief overview of how security patterns and practices have evolved in the past months, dive into some details of recent developments, and talk about promising projects and their plans for the future.
Devcon
Talk
21:00
The Melon security approach
Melonport is striving to build a vibrant and successful developer ecosystem of Melon module builders. An important part of that ecosystem is the security and behaviour of smart contracts that make up Melon modules as well as how they interact with the Melon core and each other. In this presentation, we’ll demonstrate our ongoing technical efforts to assist Melon module developers in creating safe, secure smart contracts and touch on the importance of getting the auditing process right and how others can learn from our experience.
Devcon
Breakout
24:32
Vulnerability Coordination and Incident Response in a Decentralized World
There’s one question that every team of core blockchain developers has discussed at least once: what are we going to do when a critical vulnerability in our software is surfaced? By definition, everything we create is likely to include a vulnerability or code flaw and the difficult legal, ethical, and business issues arise when bugs show up in code. While decentralization does not require us to reinvent the first principles security, it does force us to challenge ourselves to manage significant complexity to reduce harm to those who depend on our code. This talk will discuss the CosmosCERT as a model for how teams can successfully coordinate vulnerabilities and respond to incidents in decentralized environments using on-chain governance mechanisms in a way that ensures stakeholders have a dedicated emergency response capabilities ready to go when the worst happens.
Devcon
Talk
29:23
Smart Contract Security - Incentives Beyond the Launch
To mitigate security issues that were quickly present in the deployment of smart contracts, the community has turned to a wide variety of security techniques. Standard when deploying new contracts is manual review by an externally contracted company/individual. In many ways this has been a success, reducing the number of observed security incidents. In this talk, we take a look at how unique incentives in smart contracts affect the process of securing them. For example, smart contracts are often non-upgradeable: enshrinement at release time encourages security processes that end after the deployment of the contract, leaving blind spots in long-term security guarantees against evolving threats. Pressure to ship often leaves critical security guarantees out-of-scope of external reviews, and auditor incentives tend away from detailed or fundamental criticisms of contracts' protocols. In this talk, we review the reviews and take a look at several top contracts in the ecosystem: what are the provided guarantees, who were they reviewed by, and what is missing? How do these guarantees compare to guarantees provided users in systems outside the smart contract ecosystem? And how can we most effectively deploy the immense talent coming into the community towards more secure, more usable systems for end-users?
Devcon
Breakout
23:05
Batched Bonding Curves: Grieving DEX Frontrunners
It's been widely publicized that front-running is rampant across decentralized exchanges. Billy Rennekamp describes the technique developed to stop the parasitic behavior by using batched orders in tandem with bonding curves and how it's being used in a new fundraising app by Aragon Black.
Devcon
Breakout
27:10
(Defense Against) The Dark Arts - Contract Runtime Mutability
Smart contracts are no longer guaranteed to have immutable runtime code, and can be redeployed with new code using a variety of methods involving the CREATE2 and SELFDESTRUCT opcodes. In this presentation, we will investigate how this is done and how to protect against malicious mutable contracts. We will also explore ways these new techniques can be applied in order to enable new use-cases and to improve the user experience.
Devcon
Breakout
18:25
Fuzzing the Solidity Compiler
Since the Solidity programming language does not have a formal specification, testing the compiler implementation is an important way to obtain assurance about the correctness of code generated by the compiler. Fuzz testing is well-suited for this setting. However, applying fuzzing in the traditional manner (random input generation that is coverage-guided) is inefficient for testing compilers because a significant fraction of randomly generated code is syntactically invalid. If the fuzzer does not generate syntactically correct Solidity programs, the compiler will simply reject it. As a consequence, code optimization and generation subsystems of the compiler will not be tested. The approach adopted by us is to define a grammar for the Solidity programming language and automatically generate inputs based on this grammar. Grammar based fuzzing ensures that generated programs are successfully parsed by the front-end parser. We make use of libProtobuf and libProtobufMutator for defining the grammar and performing grammar-based mutations, and libFuzzer as the underlying fuzzing engine.
Devcon
Breakout
05:40
Keymanagement: Multisig based Custody as Enabler for Mass Adoption
Key management is a fundamental challenge in the widespread use of blockchain technology. Especially when it comes to managing large tokenized values, a suitable custody service is essential. While many existing custody services are primarily based on technologies such as Shamir's Secret Sharing, it makes sense to use a Smart Contract based Multisig to manage the rules such as access, what signatures are required, time delay, recovery of lost accesses, etc.
Devcon
Breakout
05:17
Securely storing wallet private keys for application use
Private key management is a complex problem in cryptography. In the last few years, we have seen attacks against cryptocurrency companies that seek to retrieve the private keys of user wallets. Within cryptocurrency, private key management has an additional complexity: the value of stored user funds related to that private key. Truly, key management is a challenge that has plagued secure computing for years.While storing keys is essential, it is equally important to securely use those keys in an application. Without secure use of private keys, applications are vulnerable to attacks to exfiltrate those private keys.In this talk, we will discuss the approach the AirSwap team uses to securely store and use private keys for high value wallets. We will show real world permissions, policies, and code used by our team. We will discuss common attacks against private key management systems and the ways that our implementation thwarts those attacks.This talk is beneficial to any team or company that interacts with the Ethereum blockchain via signed transactions and off-chain custom code. It is essential for any team that wishes to use a private key in their application code securely.