CISA + G7 Publish a Post-Quantum Call to Action: Harvest-Now-Decrypt-Later Is Officially on the Clock

What was published (yesterday)//

On September 3, CISA and the G7 Cyber Security Working Group released Preparing for the Post-Quantum Era: A Call to Action, with CISA's resource page carrying the summary and link to the full document. The G7 working group "recognize[s] the growing threat that quantum computing poses to public-key cryptography" — while conceding the exact timeline is uncertain, recent advances suggest an anticipation of quantum computers able to break widely used public-key mechanisms.

The five priorities for a successful transition to post-quantum cryptography (PQC), verbatim from CISA's page:

1. Raising awareness of quantum risks and the importance of PQC;
2. Developing national strategies that support PQC adoption and integration;
3. Advancing research and development for quantum-safe technologies;
4. Fostering public-private partnerships to share expertise and resources; and
5. Integrating PQC into cybersecurity requirements and procurement processes.

That's the whole document in a paragraph: start now, coordinate nationally, buy accordingly. No "patch by X" dates, no KEV-style deadlines — resist anyone who sells you urgency this doc doesn't contain. It is explicitly a posture shift, not an order of battle.

The part that's actually about you: HNDL//

The threat model that makes PQC urgent before a big quantum computer exists is harvest-now-decrypt-later (HNDL): collect encrypted traffic and long-lived credentials today, hold them, and decrypt the interesting ones when the hardware arrives. The doc doesn't need to name it for you to recognize your own exposure — HNDL targets anything that stays secret for a long time:

• SSH keypairs that have signed into your lab since 2021
• Full-disk encryption keys on NAS boxes and laptops
• TLS certificates for internal services (the ones nobody audits because "it's only internal")
• Long-lived API tokens, signing keys, and anything in a secrets manager that never rotates

Self-hosters hold these in bulk — often years without rotation. That's precisely the collector's dream: one compromise of your long-lived SSH key is not just today's access, it's a decade of decryptable history waiting on someone else's shelf.

What to do about it (inventory first)//

The doc gives governments and industry five strategic priorities; for a homelab the translation is an inventory, because you can't transition what you don't know you have:

1. List your long-lived secrets. Every SSH keypair, FDE passphrase, internal TLS cert, and static token — with its age and who/what uses it. A spreadsheet is fine; the point is that "when did this last rotate?" has an answer for each row.
2. Rotate the old ones on a schedule you'll actually keep. Rotation doesn't fix HNDL retroactively (the collector already has the ciphertext), but it caps how much history one leaked key exposes — and it's the cheapest quantum-prep there is.
3. Note where hybrid encryption shows up. PQC migration in practice lands as hybrid schemes (classical + post-quantum KEM, e.g. X25519MLKEM768 in TLS 1.3). When your distro or CA starts offering them, that's the transition arriving — your inventory tells you which boxes to flip first.
4. Watch the procurement line. Priority #5 (PQC in requirements) is where this becomes a vendor question: new gear and software should be evaluated on whether it can do hybrid PQC without a re-architecture later.

The honest take//

This is a good document doing what posture documents do: it names the direction without pretending to have the timeline. The G7 admits the quantum clock is uncertain, and that honesty is why you shouldn't panic-buy anything this week. But "posture shift" has always been government-speak for the budget cycle just changed — expect PQC requirements to show up in procurement language within a year or two, and expect the hybrid-KEM stuff to start appearing in default builds before anyone writes an advisory about it.

The one concrete action that earns its keep tonight: inventory the long-lived keys. Everything else is downstream of knowing what you're holding.