Solana Co-Founder Criticizes Ethereum’s L2 Security Model as ‘Fundamentally Broken’

Ethereum’s layer-2 (L2) ecosystem is under intense scrutiny following a public disagreement between two of the industry’s most influential figures — Ethereum co-founder Vitalik Buterin and Solana co-founder Anatoly Yakovenko. The debate centers on the true security of Ethereum’s L2 architecture, which currently secures more than $35 billion in total value locked (TVL).

While Buterin maintains that L2s safely inherit Ethereum’s security guarantees, Yakovenko argues that the model remains deeply flawed at its core. The dispute has reignited a long-standing question within the blockchain community: are L2s as secure as Ethereum’s main chain, or do they expose users to hidden risks?

Buterin’s Confidence in Ethereum’s L2 Security

Buterin has long defended Ethereum’s modular scaling vision — a structure where L2s handle transactions off-chain but rely on Ethereum’s base layer for final settlement and protection.

In his latest comments, Buterin reiterated that L2s are not vulnerable to 51% attacks because they ultimately depend on Ethereum’s validator network for finality. With over one million validators securing the chain, he believes L2s maintain the same trust assumptions as the base layer.

However, Buterin did acknowledge that risks may emerge if individual L2s expand their validator responsibilities beyond Ethereum’s direct control. When that happens, he warned, the connection to Ethereum’s security guarantees can weaken, potentially exposing users to new threats.

Still, he remains confident that Ethereum’s current design offers a superior path to scalability without sacrificing decentralization.

Yakovenko’s Counterpoint: A “Fundamentally Broken” Model

Yakovenko, on the other hand, took a firm stance against this view. He dismissed Buterin’s confidence as misplaced, calling Ethereum’s L2 model “fundamentally broken.”

In a post shared on X (formerly Twitter), the Solana co-founder argued that despite years of progress, Ethereum’s L2s continue to face the same systemic risks that plague cross-chain bridges — an area notorious for security breaches and billions in lost funds.

He outlined three main flaws in existing L2 designs:

1. Complex Code and Attack Risk: Yakovenko claimed that the sheer complexity of L2 smart contracts increases the chance of exploitable bugs and vulnerabilities.

2. Multi-Signature Custody Concerns: Many L2s rely on multi-signature arrangements that can, in theory, move user funds without consent. This design, he argued, compromises trustless security.

3. Off-Chain Processing and Centralization: The reliance on off-chain sequencers and operators concentrates power in a few hands, creating potential points of failure.

He even proposed an unconventional solution — creating a special interoperability bridge that would allow Ethereum to function as a layer-2 for Solana. Such a move, he suggested, could make Ethereum more efficient while addressing what he perceives as its deep-rooted L2 security challenges.

Ethereum Developers Push Back

Not everyone agreed with Yakovenko’s assessment. Ethereum developers and supporters quickly responded, arguing that his claims overlooked significant ongoing improvements to the L2 ecosystem.

One Ethereum contributor emphasized that “nothing fundamental” prevents L2s from inheriting full L1-level security. According to them, newer Stage 2 L2s already act like “vault contracts” on Ethereum, meaning all withdrawals and settlements are ultimately enforced by the base chain.

They added that continuous upgrades—such as improved fraud proofs, validity proofs, and enhanced interoperability—are steadily closing any existing security gaps.

Still, Yakovenko was unconvinced. He doubled down, insisting that there remains a fundamental challenge preventing L2s from achieving true Ethereum-level safety, even after half a decade of experimentation.

The Broader Context: ETH vs. SOL

The debate comes at a time when Ethereum and Solana are both experiencing renewed investor interest. Over the past year, the two networks have largely mirrored each other’s market movements. Ethereum has gained roughly 15.4%, while Solana has climbed 7.3%, according to TradingView data.

Both assets saw mid-year rallies driven by network upgrades and increased adoption but faced pullbacks in September before stabilizing into late October.

While Ethereum continues to dominate decentralized finance (DeFi) and layer-2 development, Solana has built its reputation on high throughput and cost efficiency, positioning itself as a “monolithic” alternative to Ethereum’s modular approach.

Why the Debate Matters

This public clash between Buterin and Yakovenko isn’t just philosophical — it highlights the divergent visions shaping the future of blockchain infrastructure.

Ethereum’s modular model focuses on separating functions like execution, consensus, and data availability across different layers. This enables flexibility and scalability but introduces dependencies between the main chain and external rollups.

Solana, in contrast, takes an integrated approach, keeping all core functions on a single chain to minimize complexity and latency. Yakovenko’s criticism stems from this belief that Ethereum’s modular scaling introduces unnecessary attack surfaces and centralization vectors.

As more capital flows into L2s like Arbitrum, Optimism, Base, and Worldchain — which collectively hold over $35 billion in assets — questions about security inheritance are becoming increasingly relevant. Any major breach could have a ripple effect across the entire Ethereum ecosystem.

The Road Ahead

The discussion between Buterin and Yakovenko underscores a key tension in blockchain design: scalability versus simplicity. Ethereum’s roadmap continues to prioritize modular scaling through L2s and data-sharding, while Solana maintains its focus on performance within a single-layer system.

For now, Ethereum’s L2s remain central to its ecosystem, driving innovation in areas like gaming, payments, and decentralized finance. Yet, as the conversation shows, the debate over whether these networks are secure enough is far from settled.

Both founders appear to agree on one thing — the blockchain world is still far from achieving a perfect balance between speed, cost, and trust.