The stablecoin MSUSD has crashed by 90%: a conflict with the auditor and a chain reaction in DeFi.
On June 20, 2026, the "stablecoin" MSUSD from the Main Street project lost its peg to the US dollar. The asset's price collapsed by more than 90%, falling well below the target mark of $1. This event dealt a serious blow to confidence in the project and triggered a chain reaction in the DeFi ecosystem.
Cause of the Collapse: Break with Reserve Provider
The key trigger for the depeg was a conflict with the reserve verification service Accountable. The company unilaterally terminated its cooperation with Main Street, citing the protocol's non-compliance with verification standards. Immediately after the monitoring was disconnected, the MSUSD rate crashed, as confirmed by data from analysts at PeckShieldAlert.
The Main Street team described the incident as a technical reporting issue and stated that the assets are fully backed. To stabilize the situation, the developers allocated $8 million in USDC to support liquidity and began searching for a new auditor. However, the market reacted extremely negatively.
Domino Effect: Closure of the $39 Million Altura Fund
The incident sparked panic in other DeFi services. The Altura protocol announced the closure of its main vault worth $39 million due to a mass withdrawal of funds. Within 24 hours, users withdrew over $8.5 million in USDT. Project head Ranvir Arora explained that Altura had no direct investments in MSUSD, but both protocols used the same auditor — Accountable. This caused distrust in Altura's stability.
The Altura team has begun a gradual return of assets to users, but the process will take time, as some funds are placed in long-term strategies and real-world assets (RWA). Other products of the protocol continue to operate normally.
Recall that back in May 2026, the total market capitalization of stablecoins hit an all-time high, reaching $323 billion. The MSUSD incident is a serious wake-up call for the entire industry. Dependence on a single auditor and the lack of reserve transparency remain the Achilles' heel of many DeFi projects. The market urgently needs a more reliable verification infrastructure, otherwise such collapses will become a systemic threat.