Stablecoin Depeg Risk Ranked: USR Failed, USD0++ Hit $0.89,…

KEY TAKEAWAYS

1. USR crashed over 95% after an attacker exploited a compromised private key to mint 80 million unbacked tokens, then extracted approximately 24 million dollars in ETH from the Resolv protocol. The token fell to about $0.025 at its lowest point.
2. USD0++ depegged to $0.89 after Usual Protocol introduced a discounted floor redemption price, revealing that the token actually functioned as a four-year locked bond rather than a liquid redeemable stablecoin.
3. USDC earned an S&P Global stability rating of 2, designated as Strong, with $75.88 billion in reserves as of October 2025, split across 35% Treasuries, 53% repurchase agreements, and 12% cash, with regular monthly Deloitte attestation.
4. Webacy research found that solvency failures, including unbacked mints like USR or reserves that were claims on failed counterparties, caused 72% of the $2.5 billion destroyed across 36 loss-bearing stablecoin collapses from 2022 through 2026.
5. The GENIUS Act, signed into law in July 2025, requires a 1:1 reserve backed by approved liquid assets, monthly reserve composition reports, and priority claims for qualifying stablecoin holders during issuer insolvency proceedings.

 The stablecoin market now exceeds $307 billion in total capitalization across blockchains, according to DeFiLlama's September 2026 data. Recent collapses reveal that stablecoin depeg risk varies considerably across token issuers. Some tokens maintain robust reserves while others harbor serious structural design flaws.USR lost over 95% of its value after one private key exploit. USD0++ dropped to $0.89 when Usual Protocol changed its redemption mechanism, and USDC holds an S&P rating of 2 with transparent and audited reserves.Webacy data shows solvency failures, including unbacked mints like USR or reserves that were claims on failed counterparties, caused 72% of the $2.5 billion destroyed across 36 loss-bearing stablecoin collapses from 2022 through 2026.The GENIUS Act now requires issuers to maintain a 1:1 liquid reserve backing. This ranking examines three stablecoins across depeg probability and overall reserve quality.

How USR Collapsed After a Key Compromise Exploit

Resolv Labs issued USR as a delta-neutral stablecoin pegged to one dollar. The token used derivatives positions to maintain its peg against ongoing volatility. On March 22, 2026, an attacker exploited a compromised private key vulnerability.The attacker deposited up to $200,000 in USDC into the minting smart contract. Using the compromised key, 80 million unbacked USR tokens were minted. The attacker swapped these tokens and extracted approximately $24 million in ETH. USR crashed over 95% to about $0.025 within hours of the exploit occurring. The broader market saw a crypto bloodbath as panic spread across exchanges.CoinDesk reported that USR's market confidence evaporated almost entirely within one period. Blockaid analysis revealed the root cause was not a smart contract bug, and the system lacked upper bounds on minting and robust on-chain verification safeguards. The incident reflected weaknesses in key management procedures.Blockaid reported that the protocol managed approximately $141 million in collateral after the exploitation. The exploit only affected newly minted tokens, not previously deposited user funds.Webacy classified USR's collapse as a solvency failure. Its research found that solvency failures, including unbacked mints like USR and reserves tied to failed counterparties, caused 72% of the $2.5 billion destroyed across 36 loss-bearing stablecoin collapses from 2022 through 2026. USR's collapse illustrates why key management remains critical for stablecoin protocol security.Investors holding USR at the time of exploitation faced near-total value losses. Recovery prospects remain uncertain because the token has not regained its peg. The incident underscores growing calls for mandatory on-chain verification in stablecoin minting. The exploit shows how single points of failure can destroy stablecoin ecosystems.

Why USD0 Carries Structural Depeg Vulnerabilities

Usual Protocol issues USD0, a stablecoin backed by short-term US Treasury bills. USD0++ is its liquid staking derivative with a four-year lock-up period attached. The distinction between USD0 and USD0++ is critical for understanding depeg dynamics.In January 2025, USD0++ fell sharply to a range between $0.89 and $0.92. Usual Protocol introduced a new exit mechanism with $0.87 floor pricing. USD0++ functioned more like a four-year locked bond than a freely redeemable stablecoin.The USUAL governance token declined 18.7% within 24 hours of the depeg. Pendle and Morpho decentralized finance positions were directly affected by this. Blockworks reported that DeFi protocols scrambled to adjust USD0++ risk parameters.Usual Protocol responded by introducing a Revenue Switch and an early unstaking option. OneSafe noted these measures aimed to restore confidence among existing token holders. The protocol faced criticism for poor communication about USD0++'s structural characteristics.The USUAL token currently trades at approximately $0.015 per single token unit. CoinMarketCap data shows USUAL's market capitalization has declined to roughly $30 million. Neither S&P Global nor Bluechip currently rates USD0 or USD0++ for stability.The absence of independent ratings leaves investors without an objective USD0 risk assessment. Structural complexity in staking derivatives creates hidden risks surfacing only during stress. USD0's case demonstrates how token design choices can embed latent depeg vulnerabilities.Investors considering USD0++ should recognize its bond-like structure before allocating capital. The four-year lock period creates liquidity risk that standard assumptions cannot capture. Redemption floor mechanics introduce price discovery dynamics absent from traditional peg designs.Market analysts continue monitoring whether Usual Protocol's adjustments address structural concerns. The token's future depends on regaining investor trust through transparent governance practices.

USDC Maintains Low Risk Through Reserve Transparency and Regulation

S&P Global assigned USDC a stability rating of 2, designated as Strong. The agency gave USDC an Asset Assessment of 1, meaning Very Strong. Bluechip independently rates USDC at B+, confirming its top-rated stablecoin position.As of October 2025, Circle's reserve composition totaled $75.88 billion, according to the S&P Global assessment. Roughly 35% sat in Treasuries, 53% in repurchase agreements, and 12% in cash. BlackRock manages the Circle Reserve Fund, holding these underlying reserve assets.Deloitte provides monthly attestation reports verifying USDC's reserve backing and composition details. These reports are publicly available, giving investors regular visibility into reserves. This transparency distinguishes USDC from issuers lacking independent third-party reserve verification.USDC depegged notably in March 2023 following the Silicon Valley Bank collapse. Circle held $3.3 billion at SVB, causing USDC to trade at $0.87. The peg recovered once the Federal Reserve backstopped all SVB deposit holders.Adoption of regulated stablecoins has grown considerably since the SVB episode unfolded. Mohamed Damak of S&P Global noted significant risk differences across stablecoin issuers. S&P noted that bankruptcy protection uncertainty remains a caveat for USDC's rating.Christoph Hock of Union Investment described USDT and USDC as "speculative hedge funds" in comments reported by CoinDesk. Disruption Banking reported institutional USDC adoption continues accelerating through 2026 overall. Circle's regulatory compliance positions USDC favorably under the new GENIUS Act framework.Despite strong ratings, USDC carries residual risk in extreme market stress conditions. Banking concentration and custodial risks remain factors S&P continues monitoring closely. Even top-rated stablecoins carry some residual risk during broader systemic market crises.Reserve quality and transparency make USDC the benchmark for stablecoin risk assessment. Continued regulatory alignment should further strengthen USDC's position in global stablecoin markets.

Regulatory Implications

The GENIUS Act was signed into federal law in July of 2025. It requires a 1:1 reserve backing with approved assets for all stablecoin issuers, and monthly reserve composition reports apply to all issuers, while annual audited financial statements are required for issuers with more than $50 billion in outstanding stablecoins.The OCC issued its Notice of Proposed Rulemaking implementing parts of the GENIUS Act on February 25, 2026, with the proposal published in the Federal Register on March 2, 2026. The GENIUS Act excludes payment stablecoins from the definitions of securities and commodities and provides priority claims for qualifying stablecoin holders during issuer insolvency proceedings.

What's Next?

The OCC is currently finalizing its implementation rules under the GENIUS Act. S&P Global continues expanding stablecoin assessments, having rated 11 tokens so far. Federal Reserve research has flagged run risk propagation as a systemic concern. Stablecoin markets will likely see increased regulatory scrutiny and standardized disclosures ahead.

FAQs

What caused USR to depeg? An attacker exploited a compromised private key to mint 80 million unbacked USR tokens, then extracted roughly $24 million in ETH from the Resolv protocol.What is USD0++ exactly? USD0++ is a liquid staking derivative of USD0 with a four-year lock period, issued by Usual Protocol and backed by US Treasury bills through underlying reserves.How safe is USDC? USDC holds an S&P stability rating of 2, designated Strong, with $75.88 billion in reserves as of October 2025, according to S&P Global. Deloitte provides monthly attestations, while BlackRock manages the Circle Reserve Fund.What does the GENIUS Act require? The GENIUS Act requires stablecoin issuers to maintain a 1:1 reserve backing with approved liquid assets and publish monthly reserve composition reports. Annual audited financial statements are required for issuers with more than $50 billion in outstanding stablecoins.Why did USD0++ lose its peg? Usual Protocol introduced a discounted floor redemption price of $0.87, revealing that USD0++ functioned as a four-year locked bond rather than a liquid stablecoin.What is a stablecoin depeg? A stablecoin depeg occurs when the token's market price falls significantly below its intended peg value, typically due to structural, operational, or broader market failures.Who rates stablecoin stability officially? S&P Global publishes stablecoin stability assessments, rating reserve quality and governance, while Bluechip provides independent security ratings for major stablecoin tokens across decentralized finance markets.

References

1. CoinDesk report: Resolv Stablecoin Drops 70% After $80 Million Exploit
2. S&P Global: Stablecoin Stability Assessments
3. Webacy research: Stablecoin Depeg Failure Mechanisms
4. GENIUS Act (S.1582): Full Text