Ethereum’s co-founder Vitalik Buterin has shed light on some of the significant concerns surrounding Worldcoin’s novel identity verification system, which recently launched its WLD token. Buterin’s critique focused on four primary areas of potential risk within Worldcoin’s Proof-of-Personhood (PoP) model, and he proposed an alternative solution to mitigate these issues.

Vitalk Buterin Worldcoin

The Functionality of Worldcoin’s PoP Model

Worldcoin employs a biometric-based PoP system that validates the uniqueness of a user in a decentralized manner, thereby eliminating the need for a centralized authority and minimizing the revelation of personal data. Notable applications of this system include safeguarding against Sybil attacks by inhibiting multiple account creation, airdrops, event ticketing, and DAO voting. The process involves iris scanning by a device named “Orb,” which subsequently verifies a user’s humanity and the uniqueness of the iris to create a unique World ID.

Buterin’s Insight on Worldcoin’s PoP Construction Risks

Buterin’s scrutiny of the PoP system highlighted four primary risks: privacy, accessibility, centralization, and security.


Despite the hashing of iris scans and the use of ZK-SNARKs and other cryptographic methods for user identity protection, Buterin expressed concerns about the misuse or potential leak of identity-related information. He pointed out the possibility of an individual’s iris scan being cross-referenced against the database to determine the existence of a World ID.


The accessibility of Worldcoin’s Orb device is another issue. Buterin believes that the necessity for physical access to an Orb may limit the project’s reach, creating a distribution imbalance favoring areas with a higher concentration of Orbs.


Centralization is another area of concern. Buterin argues that the integrity of Orb’s hardware cannot be independently verified, which raises the possibility of backdoors and fake identities. Although Worldcoin intends to decentralize over time, Buterin notes the proprietary algorithms and governance structure as points of centralization concern.


Buterin also called attention to security risks such as phone hacking, ID selling or renting, and the use of 3D-printed “fake people” to trick the system.

Despite these identified risks, Buterin acknowledged the value of the concept behind Worldcoin, and the potential risks of not having any proof-of-personhood systems at all.

Buterin’s Proposition

Buterin posits that merging the three existing PoP approaches—social-graph-based, general-hardware biometric, and specialized-hardware biometric techniques—could provide a secure, scalable, and privacy-conscious system that offers robust protection against fake identities. This comprehensive solution could potentially address the risks associated with Worldcoin’s approach.


The launch of Worldcoin’s WLD token marked a significant event in the world of cryptocurrency. However, Vitalik Buterin’s critique brings into focus the potential pitfalls of its PoP model. It will be interesting to see how Worldcoin addresses these concerns as it seeks to revolutionize digital identity verification through blockchain technology.