Solana Foundation removes certain operators from delegation program over malicious sandwich attacks

The Solana Foundation announced it removed a group of validator operators from its delegation program due to their involvement in sandwich attacks on Solana users.

“Decisions in this matter are final. Enforcement actions are ongoing as we detect operators participating in mempools which allow sandwich attacks,” wrote Solana Validator Relations Lead Tim Garcia on the Solana Foundation’s Discord server.

The move will ensure that the foundation does not delegate to validators who carry out malicious sandwich attacks on retail users, explained Mert Mumtaz, co-founder of Solana RPC provider Helius.

Sandwich attacks are against the rules laid out by the Solana Foundation in a May 7 Discord post from Garcia.

A sandwich attack is a type of front-running exploit where an attacker places two transactions around a victim’s transaction to manipulate the price and profit from the difference. 

“Operators engaging in malicious activities such as participating in a private mempool to sandwich attack transactions or otherwise harming Solana users will not be tolerated by the delegation program. Anyone found engaging in such activity will be rejected from the program and any stake from the Foundation will be immediately and permanently removed.”

Garcia specifically referenced this when making the announcement of the operators being removed.

The Solana Foundation Delegation Program was put in place to help validators operate by delegating SOL tokens to them, removing the need to hold a substantial amount of tokens. Validators are selected based on performance.

However, the participation comes with certain caveats and expectations of good practices. As Solana is a permissionless network, the operators can still contribute to the blockchain, but they will no longer be subsidized with SOL staked to them by the foundation.

On Solana, MEV ( Maximal Extractable Value ) issues arise when validators manipulate transaction ordering to maximize profits. This includes front-running and sandwich attacks, where validators exploit transactions to profit from price changes, causing higher costs and slippage for users.