Finance & Banking PQC Solution

Financial systems combine long-retention secrets, regulated cryptography, and a deep dependence on Shor-vulnerable public-key algorithms. That makes banking one of the first sectors that must act on post-quantum migration — both to defeat "harvest now, decrypt later" attacks and to stay compliant with China's commercial-cryptography regime.

Why act now

The drivers in finance are simultaneously a threat and a compliance obligation:

• HNDL on long-lived data. Account records, transaction histories, KYC/identity material, and contracts retain value for 10–30 years. An adversary can record today's TLS/IPsec sessions or exfiltrate ciphertext now and decrypt it once a cryptographically relevant quantum computer (CRQC) exists. By Mosca's inequality (X+Y>Z), if secrecy lifetime plus migration time exceeds the time to a CRQC, you are already exposed.
• 商用密码合规 & 密评. Under the Cryptography Law (effective 2020-01-01, SCA), commercial-cryptography application security assessment (密评, per GB/T 39786-2021 and GM/T 0115/0116-2021) is mandatory for CII, 等保 level-3+ systems, and important government/finance systems, with annual re-assessment.
• CII crypto requirements. GM/T 0133-2024 (effective 2025-07-01) raises crypto requirements for critical information infrastructure — most large banks operate CII.
• Sector & cross-border rules. PBoC / financial-industry JR/T standards govern domestic crypto usage; PCI DSS and GDPR apply to cross-border payment and data flows. 等保三级 (MLPS level 3) applies to core financial systems.

Risk & asset map

Symmetric primitives (SM3/SM4/ZUC, AES) are only weakened by Grover and are mitigated with larger sizes (AES-256, ZUC-256). The urgent targets are the Shor-broken asymmetric layers (SM2/SM9, RSA/ECC/ECDSA).

Recommended architecture

The design goal is crypto-agility: replace hard-coded algorithms with negotiable, swappable suites so future parameter changes do not require re-architecting. Build on the patterns in construction-blueprint.html.

• Hybrid key exchange. Combine a classical exchange (ECDH or SM2) with ML-KEM via a KDF, so a session stays secure if either component holds. This preserves 国密 compliance while adding quantum resistance — see hybrid.html.
• Dual signatures. Sign with both a classical scheme (SM2 or ECDSA) and ML-DSA, giving verifiable backward compatibility and post-quantum integrity.
• PQC-ify PKI & HSM. Issue hybrid/PQC certificates, add PQC support in HSM firmware and key-management, and plan for larger key/signature sizes. See pki.html.
• High-assurance reference. CNSA 2.0 (ML-KEM-1024 + ML-DSA-87) is a useful upper-bound profile for the most sensitive flows.
• Inventory first. No migration without a cryptographic bill of materials — see discovery.html and the quantum-risk-model.html.

Phased roadmap

Reference cases

Synthesized from the 2025 安全牛 report on the cn-vendors.html page: 银河证券 ran an anti-quantum pilot (with Koal / 格尔软件), and a digital-currency exchange deployed a hybrid scheme combining classical and PQC key exchange. These confirm that hybrid-first, pilot-led migration is the practical CN-finance path.

KPIs & success criteria

• 100% cryptographic asset coverage in the inventory; every Shor-vulnerable asset risk-scored.
• 密评 readiness with no critical findings against GB/T 39786 / GM/T 0133-2024.
• Hybrid key exchange live on all external payment/transaction channels by end of Phase 2.
• Dual-signature coverage on core-banking and CBDC flows; PQC-capable HSM/PKI in production.
• Legacy pure-classical asymmetric crypto retired on a published decommission schedule.

Standards & references

• GM compliance — 密评 & commercial cryptography — GB/T 39786-2021, GM/T 0133-2024, 《密码法》.
• Hybrid key exchange & dual signatures
• PQC-ready PKI and cryptographic discovery
• Quantum risk model and CN vendors & reference cases
• Resources — full standards register