Is Fifth Third quantum-safe?
Partly. 5 of 104 public servers under 53.com use post-quantum key exchange, the protection against traffic recorded today being decrypted once a large quantum computer exists. Grade C. Scanned October 18, 2026.
Fix first
Production login, API, VPN, payment and developer servers that still rely on key exchange scheduled for retirement.
- account.53.com
- accounts.53.com
- admin.53.com
- api-v2.53.com
- api.53.com
- api2.53.com
- app.53.com
- auth.53.com
- developer.53.com
- developers.53.com
- fleet.53.com
- gateway.53.com
- gw.53.com
- mobile.53.com
- ota.53.com
- partner.53.com
- partners.53.com
- pay.53.com
- payments.53.com
- portal.53.com
- remote.53.com
- telemetry.53.com
- update.53.com
- updates.53.com
75 other servers without post-quantum key exchange
- affiliate.53.com
- analytics.53.com
- assets.53.com
- beta.53.com
- blog.53.com
- careers.53.com
- cdn.53.com
- checkout.53.com
- ci.53.com
- cloud.53.com
- console.53.com
- dashboard.53.com
- data.53.com
- demo.53.com
- dev.53.com
- docs.53.com
- edge.53.com
- event.53.com
- events.53.com
- exchange.53.com
- futures.53.com
- git.53.com
- gitlab.53.com
- go.53.com
- grafana.53.com
- help.53.com
- images.53.com
- imap.53.com
- img.53.com
- iot.53.com
- jenkins.53.com
- kibana.53.com
- kyc.53.com
- link.53.com
- m.53.com
- mail.53.com
- metrics.53.com
- monitor.53.com
- mx.53.com
- my.53.com
- news.53.com
- ns1.53.com
- ns2.53.com
- oauth.53.com
- open.53.com
- openapi.53.com
- otc.53.com
- payment.53.com
- press.53.com
- pro.53.com
- promo.53.com
- referral.53.com
- sandbox.53.com
- sftp.53.com
- shop.53.com
- smtp.53.com
- socket.53.com
- stage.53.com
- staging.53.com
- stat.53.com
- static.53.com
- stats.53.com
- status.53.com
- store.53.com
- stream.53.com
- support.53.com
- test.53.com
- trade.53.com
- trading.53.com
- uat.53.com
- vip.53.com
- wallet.53.com
- webmail.53.com
- ws.53.com
- wss.53.com
5 servers already protected
- 53.com
- id.53.com
- secure.53.com
- sso.53.com
- www.53.com
What this means
NIST has scheduled the key exchange most servers still use for retirement: deprecated after 2030, disallowed after 2035 (NIST IR 8547). Traffic recorded today can be decrypted once a large quantum computer exists. A server that offers hybrid ML-KEM key exchange closes that today; a server that does not is still open to harvest now, decrypt later.
Hostnames come from public certificate logs plus common service names, kept where the name resolves to a public address, and each is tested from the outside with post-quantum-only TLS 1.3 handshakes. A hostname shows what a server is called, not what traffic it carries; internal systems are out of scope. Method.
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<a href="https://latticescan.com/readiness/53.com"><img src="https://latticescan.com/badge/readiness/53.com" alt="quantum readiness"></a>