No. Windows does not yet support post-quantum TLS by default. Windows CNG and SChannel use RSA and ECDH for key exchange.
Key Takeaway: Windows is NOT quantum safe. Deploy PQC-capable TLS termination in front of Windows services. Use QScout to assess current Windows TLS configuration.
Microsoft Windows is NOT quantum safe by default. The Windows SChannel TLS stack does not support post-quantum key exchange. Windows CNG does not include ML-KEM or ML-DSA implementations. All HTTPS connections, RDP sessions, SMB file shares, and LDAP/AD authentication over TLS use classical cryptography only. Microsoft is developing PQC in SymCrypt but has not shipped production support.
| Full Name | Microsoft Windows |
| Category | infrastructure |
| Quantum Vulnerability | SChannel TLS uses RSA/ECDH key exchange — vulnerable to Shor's algorithm. |
| NIST Status | Microsoft is developing ML-KEM and ML-DSA support in SymCrypt but has not shipped FIPS-aligned PQC. |
| Deprecation Timeline | Windows classical-only TLS should be supplemented with PQC proxies immediately |
| Replaced By | Pending Microsoft SymCrypt PQC release |
Deploy PQC-capable TLS termination in front of Windows services. Use QScout to assess current Windows TLS configuration.
QScout discovers every instance of Windows across your infrastructure in 7 days — with zero operational disruption. 72-hour time to first findings.