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Lead in: Secure Smart Contract Development

August 15, 2022

In our "Secure Smart Contract Development" series, we delve into the critical security aspects of smart contract development with a focus on NFT contracts. We explore a range of risks and vulnerabilities that we as developers might encounter and offer detailed strategies and best practices for mitigating these issues to enhance security and efficiency in blockchain applications.

Breaking Down: A Comprehensive Overview

This blog explores reentrancy vulnerabilities in NFT contracts, detailing both Single-Function and Cross-Function Reentrancy. It explains the risks associated with these vulnerabilities and provides developers with mitigation strategies to secure their smart contracts.

Digital signature has been widely used in smart contracts, e.g., in allowlist mint and order-book NFT marketplaces. That’s because it helps save transaction costs (off-chain sign and on-chain verification). However, the misuse of the developers also introduces risks in the NFT marketplaces. In this blog, we’d like to talk about the misuse of digital signatures in the NFT ecosystem.


About BlockSec

BlockSec is a pioneering blockchain security company established in 2021 by a group of globally distinguished security experts. The company is committed to enhancing security and usability for the emerging Web3 world in order to facilitate its mass adoption. To this end, BlockSec provides smart contract and EVM chain security auditing services, the Phalcon platform for security development and blocking threats proactively, the MetaSleuth platform for fund tracking and investigation, and MetaSuites extension for web3 builders surfing efficiently in the crypto world.

To date, the company has served over 300 esteemed clients such as MetaMask, Uniswap Foundation, Compound, Forta, and PancakeSwap, and received tens of millions of US dollars in two rounds of financing from preeminent investors, including Matrix Partners, Vitalbridge Capital, and Fenbushi Capital.

Official website: https://blocksec.com/

Official Twitter account: https://twitter.com/BlockSecTeam

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~$16M Lost: DxSale, SquidRouterModule & More | BlockSec Weekly
Security Insights

~$16M Lost: DxSale, SquidRouterModule & More | BlockSec Weekly

This weekly security report covers 5 notable attack incidents between May 25 and May 31, 2026, with combined losses of approximately $16M across BNB Chain, Ethereum, Base, Arbitrum, and Cosmos. Key incidents include the DxSale token locker exploit ($7.3M) involving three missing state updates compounded by a deployer key compromise, the SquidRouterModule exploit ($3.2M) caused by improper input validation in an Axelar Bridge integration that allowed forged cross-chain messages to drain 86 Safe wallets, and the Gravity Bridge signing key compromise ($5.4M). Other incidents involve a compromised deployer key (Stake DAO, $91K) and a vulnerable off-chain bridge backend (Alephium, $300K).

Newsletter - May 2026
Security Insights

Newsletter - May 2026

In May 2026, the DeFi ecosystem experienced three major security incidents. Echo Protocol lost ~$76.7M due to an administrator key compromise that enabled unauthorized minting of unbacked eBTC on Monad, StablR suffered ~$12.8M from a multisig governance breach leading to unauthorized stablecoin issuance, and the Verus-Ethereum Bridge incurred ~$11.7M following a type-validation failure that allowed a crafted supplemental export to be misclassified as a valid primary export.

Crypto Compliance Software Guide: Technical Frameworks & Top Tools

Crypto Compliance Software Guide: Technical Frameworks & Top Tools

FATF, MiCA, OFAC—three regulators, one question every VASP must answer: is your compliance stack built for the next audit, or the last one?