Explore the unique challenges of blockchain security in this 54-minute conference talk from the Hack In The Box Security Conference. Delve into the most common bug types found in major blockchain frameworks, gaining valuable insights and tools for effective security testing. Learn from hundreds of reported blockchain security issues, focusing on five prevalent bug types, their potential impacts, and practical testing strategies. Discover a newly released fuzzer for Substrate-based chains, demonstrated live to showcase typical vulnerabilities. Benefit from the expertise of Karsten Nohl, a renowned cryptographer and security researcher, as he shares his experience in breaking proprietary systems and testing telcos for hacking issues.