# EURC (EURC) Quantum Readiness Report

> EURC has a QRI score of 9/100 and is assessed at Stage 2 (Mitigation / Development) with medium evidence confidence.

Evaluation date: 2026-06-06. Review status: draft. Evaluated scope: Native EURC token deployments (ERC-20, SPL, Stellar Asset, SEP-41); evaluates token-specific admin/governance keys and host-chain cryptographic inheritance. Excludes bridged/wrapped representations on third-party chains..

EURC scores 9/100 (Stage 2: Mitigation / Development). As a standard ERC-20 stablecoin deployed across multiple classical blockchains, EURC inherits full ECDSA vulnerability for all user spend authorization. The token-specific quantum risk is concentrated in Circle's admin EOAs (owner, admin, pauser, blacklister, masterMinter, minters) which control minting, contract upgrades, pausing, and blacklisting via ECDSA signatures. A quantum attacker compromising any admin key could mint unlimited unbacked EURC or freeze/redirect user funds. On the positive side, EURC is highly PQ-Recoverable: as a fiat-backed centralized stablecoin, Circle can freeze off-chain redemptions, deploy new contracts, and restore balances from pre-attack snapshots. Circle has published a comprehensive Post-Quantum Security Roadmap (May 2026) for the Arc blockchain with plans to eventually upgrade smart contracts to support PQ signatures, but this roadmap provides zero production protection for EURC on existing chains as of the evaluation date. No PQ or hybrid-PQ cryptography is deployed anywhere in EURC's production scope. The score is capped by the Stage 2 cap (40), further constrained by the Readiness & Risk Cap (active production spend authorization remains entirely ECDSA-only), and the Factor Score of approximately 9.

## Core resources

- [EURC QRI report](https://qrindex.org/projects/euro-coin/): Human-readable assessment with score, stage, evidence, blockers, risks, and assurance notes.
- [EURC structured report data](https://qrindex.org/projects/euro-coin/report.json): Complete report as JSON for deterministic machine processing.
- [QRI methodology](https://qrindex.org/methodology/): Scoring model, evidence handling, readiness stages, confidence, assurance, and report status.
- [All QRI project reports](https://qrindex.org/llms.txt): Score-ranked index of every published project assessment.
- [EURC official website](https://www.circle.com): Project-maintained website.



## Evidence sources

- [Evidence source 1](<https://6778953.fs1.hubspotusercontent-na1.net/hubfs/6778953/PDFs/quantum_paper.pdf>): Public source cited by the EURC QRI assessment.
- [Evidence source 2](<https://www.circle.com/blog/preparing-blockchains-for-q-day>): Public source cited by the EURC QRI assessment.
- [Evidence source 3](<https://github.com/circlefin/stablecoin-evm>): Public source cited by the EURC QRI assessment.
- [Evidence source 4](<https://etherscan.io/token/0x1abaea1f7c830bd89acc67ec4af516284b1bc33c>): Public source cited by the EURC QRI assessment.
- [Evidence source 5](<https://llamarisk.com/research/2025-04-22t19-28-41-000z>): Public source cited by the EURC QRI assessment.
- [Evidence source 6](<https://developers.circle.com/stablecoins/eurc-contract-addresses>): Public source cited by the EURC QRI assessment.
- [Evidence source 7](<https://www.circle.com/eurc>): Public source cited by the EURC QRI assessment.
- [Evidence source 8](<https://www.circle.com/legal/mica-eurc-whitepaper>): Public source cited by the EURC QRI assessment.
- [Evidence source 9](<https://github.com/circlefin/stablecoin-evm/blob/master/doc/upgrade.md>): Public source cited by the EURC QRI assessment.