Marinade DAO Proposes Blocklisting 73 Validators to Combat Sandwich Attacks on Solana

Marinade DAO is advancing a proposal to blocklist 73 validators from its Stake Auction Marketplace (SAM) in response to widespread concerns over sandwich attacks. The vote, which has already met quorum, has two days remaining. The move is part of Marinade's broader strategy to mitigate Maximum Extractable Value (MEV) abuse and protect stakers.

Targeting Malicious Validators

The proposal seeks to exclude validators that have engaged in sandwiching—an MEV strategy where transaction ordering is manipulated for profit, often at the expense of retail traders. Marinade used Public tools and onchain data spanning multiple epochs to identify these actors. Validators were flagged if they facilitated a high number of sandwich attacks relative to their stake. The blocklist covers 73 validators collectively responsible for a significant share of staked SOL in the SAM.

Marinade DAO states that affected validators can appeal, with reinstatement possible after a one-month observation period if improvements are demonstrated. Repeat offenders would face permanent exclusion.

Impact on SAM and Staking Yields

Between epochs 680 and 735, Marinade's data revealed that 2% to 20% of SAM-delegated stake was assigned to these validators. In epoch 710, the figure reached 1.27 million SOL or 15.3% of the total stake. Analysis suggests that the removal of these validators would have reduced SAM's annualized percentage yield (APY) by an average of 0.9 percentage points, with a maximum observed decline of 4.5 percentage points.

Marinade's Broader Approach to MEV

Marinade Labs has been actively working to address MEV challenges on Solana, particularly the role of sandwiching in validator profitability. While less than 10% of SOL staked with Marinade goes to validators participating in sandwich attacks, some MEV-driven validators offer higher staking yields, redistributing their profits to stakers.

To counter unchecked MEV extraction, Marinade has proposed additional measures, including:

• A simplified delegation strategy to prioritize high-performing validators.
• A new staking protocol in beta, allowing institutional participation while ensuring compliance.
• A grant initiative to support further MEV mitigation efforts.

Solana's MEV Challenge and Future Solutions

Combating sandwiching and MEV is an ecosystem-wide effort on Solana. In a bid to address these issues, the Solana Foundation removed several validator operators from its delegation program in June last year due to their involvement in sandwich attacks on the network. This initiative highlights the broader commitment within the Solana ecosystem to maintaining fair and transparent staking practices.

According to data published by Marinade Labs, Solana's high throughput and low fees have made it a target for Miner Extractable Value (MEV) abuse. Reports show that a single validator extracted over $60 million in a month through sandwich attacks. Additionally, the dominance of Jito, Solana's primary MEV infrastructure, has further centralized MEV profits, raising concerns about transparency.

Marinade Labs suggests that Long-term solutions for Solana could involve protocol-level changes such as concurrent block producers to reduce validator control over transaction ordering, shorter block times to limit MEV opportunities, and a more transparent order flow system.