iosiro

iosiro is a specialized blockchain cybersecurity firm founded in 2017, dedicated to securing Web3 ecosystems through comprehensive security audits and assessments. Based in Rosebank, South Africa, the company has established itself as a trusted security partner for blockchain projects, exchanges, and decentralized applications.

Core Products/Services

iosiro offers three primary security services tailored to the blockchain industry:

Smart Contract Auditing: The company's flagship service provides in-depth security audits of smart contracts to identify functional and security vulnerabilities before deployment. Their expert team delivers comprehensive reports detailing findings and recommended fixes, with optional public report releases for stakeholder transparency. The audit process includes code review, fix verification, and ongoing support to ensure clients understand and properly remediate identified issues.

Penetration Testing: iosiro conducts extensive security assessments of Web3 infrastructure, including web applications, decentralized applications (dApps), APIs, and cloud environments. Their penetration testing service validates security controls, identifies vulnerabilities, and ensures adherence to current best practices across a wide range of technologies.

Threat Modeling: Through interactive workshops, iosiro helps teams identify and understand threats and mitigations in their systems or products. This proactive service improves risk management, optimizes security spending, and enhances secure design decision-making.

Key Strengths

iosiro's team brings deep expertise from traditional cybersecurity backgrounds, having previously secured critical systems for large financial institutions, telecommunications companies, and healthcare organizations. This foundation of experience in high-risk environments translates directly to their blockchain security work. The company has built and audited smart contracts that have handled hundreds of millions of dollars in assets, demonstrating their capability to secure mission-critical systems.

Notable security contributions include discovering and responsibly disclosing vulnerabilities in major blockchain infrastructure:

• OpenZeppelin UUPS Proxy vulnerability (2021)
• Polygon temporary denial of service issue (2021)
• Ondo Finance high-risk vulnerability (2022)
• Across Bridge double-spend vulnerability (2022)
• Nethermind ModExp consensus issue (2022)
• Optimism censorship bug (2023)
• Geth out-of-order EIP application denial-of-service (2024)
• Arbitrum Stylus invalid import denial of service (2025)

Notable Clients/Projects

iosiro has established long-term partnerships with leading DeFi protocols and blockchain projects. Their client roster includes Synthetix (ongoing audits since 2019), Nexus Mutual, Truth Markets, Wala, Cloudbric, and Penta Security Systems. The company has successfully audited numerous high-profile ICOs and continues to secure protocols managing significant value.

Why Choose iosiro

iosiro distinguishes itself through several key value propositions:

Expert Team: Clients work with security professionals who have years of experience securing high-risk blockchain ecosystems and traditional financial systems.

Comprehensive Process: The company doesn't just identify vulnerabilities - they guide clients through remediation, review fixes, and ensure issues are properly addressed.

Transparent Pricing: Fixed-price quotes eliminate unexpected costs and provide budget certainty.

Flexible Engagement: Services accommodate both early-stage startups and established protocols, with cryptocurrency payment options and tailored timelines.

Public Credibility: Optional public report releases provide stakeholders, investors, and exchange listing partners with transparent security validation.

Proven Track Record: With hundreds of projects secured and millions of dollars in assets protected, iosiro has demonstrated consistent excellence in blockchain security since 2017.