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90-Day Proven Post-Quantum TLS Readiness Sprint

#security #cybersecurity #vulnerabilities #cdn

Post-Quantum TLS Readiness: a 90-Day Remediation Sprint for SMBs

This is a hands-on playbook to move an SMB from “we should look at PQC” to Post-Quantum TLS Readiness in 90 days—without breaking client traffic or chasing unstable stacks. You’ll inventory crypto, pilot hybrid KEM handshakes in staging, coordinate vendors, roll out PQ-ready configs with a clean rollback, and prove success with objective metrics.

90-Day Proven Post-Quantum TLS Readiness Sprint

Executive summary

  • Why now: Cryptographically agile systems reduce migration risk when PQC is mandated by your customers or regulators.
  • What changes: TLS 1.3 stays; key exchange adds a hybrid KEM group (e.g., X25519+ML-KEM/Kyber). Signatures for certificates and mTLS can remain ECDSA/RSA for now.
  • How to do it safely: Pilot hybrids in staging, measure latency/CPU, deploy behind a feature flag / canary, and keep a fast rollback.

1) Crypto inventory: know where TLS terminates

Goal: a complete map of TLS termination points, cipher groups, cert types, mTLS use, and libraries (OpenSSL/BoringSSL/wolfSSL, language TLS stacks).

Discover TLS endpoints (infra & app) 

# List internet-facing 443 endpoints from your cloud (AWS example)
aws elbv2 describe-load-balancers --query 'LoadBalancers[*].DNSName' --output text
aws cloudfront list-distributions --query 'DistributionList.Items[*].DomainName' --output text

# Probe each host for TLS details (basic, non-intrusive)
for h in $(cat hosts.txt); do
  echo "=== $h ==="
  echo | openssl s_client -connect $h:443 -tls1_3 -servername $h 2>/dev/null \
    | awk '/^subject=|^issuer=|^Server Temp Key|^SSL-Session:/'
done
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Find code that controls TLS/certs 

# Find likely TLS/cert knobs across repos
git ls-files | xargs grep -nE 'ssl_(conf_command|ciphers|ecdh|curves|groups)|TLSv1\.3|X25519|P-256|ECDSA|rsa' || true

# Java/.NET/node hotspots
grep -RInE 'SSLContext|TrustManager|cipher|curves|X25519|TLS_ECDHE' .
grep -RInE 'HttpsURLConnection|Conscrypt|OpenSSLProvider' .
grep -RInE 'https.Agent|tls.createSecureContext|ALPNProtocols' .
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Deliverable: a CSV with service, endpoint, tls_lib, supports_tls13, cert_algo, mTLS, notes.

Free Website Vulnerability Scanner Tool Landing:

Screenshot of the free tools webpage where you can access security assessment tools.

2) Pilot hybrid KEM in staging

You’ll stand up a TLS 1.3 terminator that can advertise a hybrid group (e.g., X25519Kyber768*) if your provider/build supports it. Keep your public site on classical until tests are green.

OpenSSL 3 + OQS provider (staging)

openssl.cnf (system-wide providers so apps inherit support):

# /etc/ssl/openssl.cnf
openssl_conf = openssl_init

[openssl_init]
providers = provider_sect
alg_section = algorithm_sect

[provider_sect]
default = default_sect
oqsprovider = oqs_sect

[default_sect]
activate = 1

[oqs_sect]
activate = 1

[algorithm_sect]
# Optional: enable legacy if you still need it
# evp_properties = fips=no
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Export for the daemon environment:

export OPENSSL_CONF=/etc/ssl/openssl.cnf
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Check available groups:

openssl list -groups -provider oqsprovider -provider default
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NGINX (TLS 1.3 + hybrid groups where supported) 

# nginx.conf (staging)
ssl_protocols              TLSv1.3;
# OpenSSL "Groups" controls TLS 1.3 named groups; "Curves" for <= TLS 1.2
ssl_conf_command           Groups X25519Kyber768:X25519:P-256;
ssl_conf_command           Curves X25519:P-256; # fallback for older clients

ssl_ciphers                TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256;
ssl_prefer_server_ciphers  on;

# mTLS off for the public site; see section 4 for mTLS blocks
server {
  listen 443 ssl http2;
  server_name staging-pqtls.example.com;
  ssl_certificate      /etc/nginx/certs/site-ecdsa.crt;   # classical ECDSA
  ssl_certificate_key  /etc/nginx/certs/site-ecdsa.key;

  location /healthz { return 200 "ok\n"; }
  location / { proxy_pass http://app:8080; }
}
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Verify handshake groups 

# From a test runner with OpenSSL that knows the hybrid group name
openssl s_client -groups X25519Kyber768 -connect staging-pqtls.example.com:443 -tls1_3 -servername staging-pqtls.example.com </dev/null 2>/dev/null \
 | awk '/Server Temp Key|Protocol|Cipher/'
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If your client or CDN doesn’t yet negotiate hybrids, you’ll still succeed with X25519 fallback—exactly what you want during a pilot.

3) Certificates & mTLS considerations

Keep classical signatures for now (ECDSA P-256 or RSA-2048/3072). PQ signatures (e.g., ML-DSA/Dilithium) are not broadly deployed in browsers/OS trust stores yet. Your Post-Quantum TLS Readiness at this stage is about key exchange agility.

Issue short-lived ECDSA certs 

# Generate ECDSA P-256 key & CSR
openssl ecparam -name prime256v1 -genkey -noout -out site-ecdsa.key
openssl req -new -key site-ecdsa.key -out site.csr -subj "/CN=staging-pqtls.example.com"
# Submit CSR to your usual CA (private/public); prefer ≤90-day validity
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mTLS (internal APIs/k8s) 

# Add to an internal API listener
ssl_verify_client on;
ssl_client_certificate /etc/nginx/certs/mtls-ca.crt;  # classical CA for now
# Optional, stricter verification depth/policy:
ssl_verify_depth 2;
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Rotation plan: re-issue leafs on a 60–90-day cadence; pin by SPKI where your clients support it; document a dual-chain strategy if you have pinned intermediates.

4) Performance testing & budgets

Set a clear baseline vs. classical TLS.

# Baseline on classical
wrk -t4 -c200 -d60s https://staging-classical.example.com/

# Hybrid pilot
wrk -t4 -c200 -d60s https://staging-pqtls.example.com/

# Record p50/p95 latency deltas and CPU (exporter/telemetry snapshots)
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Automate in CI:

# .github/workflows/pqtls-check.yml
name: pqtls-check
on: [workflow_dispatch, schedule]
jobs:
  latency:
    runs-on: ubuntu-latest
    steps:
      - name: Baseline
        run: |
          curl -s -o /dev/null -w "baseline:%{time_total}\n" https://staging-classical.example.com/healthz
      - name: Hybrid
        run: |
          curl -s -o /dev/null -w "hybrid:%{time_total}\n" https://staging-pqtls.example.com/healthz
      - name: Assert budget (≤ 10% slower at p95)
        run: |
          # simple budget gate; replace with your metrics source
          :
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Budgets: Start with ≤10% p95 latency regression and ≤15% CPU overhead at the edge. Adjust after real data.

5) Vendor attestations (simple, enforceable)

Ask every CDN, WAF, LB, API GW, mTLS client library:

vendor: Example CDN
contact: pq@vendor.com
tls13_supported: true
hybrid_kem_groups:
  - X25519Kyber768: pilot_in_Q1
  - X25519: ga
cert_algos_supported:
  leaf: [ECDSA_P256, RSA_2048]
  client_mtls: [ECDSA_P256]
rollback_plan: "toggle to classical within 5 minutes via config flag"
evidence_link: "change ticket #1234 + packet captures"
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Keep these in your CMDB and require updates during QBRs.

6) Policy updates & training

  • Crypto agility policy: document supported TLS versions, groups, cert algorithms, rotation SLAs.
  • Runbook: exact steps to flip feature flags between hybrid/classical, with owner + pager.
  • Developer training: how client stacks negotiate groups; how to avoid hardcoding legacy ciphers.

7) Day-30/60/90 milestones

Day 30 — Inventory & pilot ready

  • Complete TLS inventory & risk register entries for Post-Quantum TLS Readiness.
  • Staging hybrid endpoint up with canary tests & CI checks.
  • Draft policy + rollback runbook.
  • If you need help accelerating discovery, use our Risk Assessment Services to formalize the gaps and plan.

Day 60 — Pilot proven

  • p50/p95 latency, CPU, and error rates within budget.
  • mTLS internal paths validated (classical certs; no client breakage).
  • Vendor attestation file completed for edge/CDN/LB.
  • Draft change ticket for production rollout.

Day 90 — Production rollout with guardrails

  • Roll out to ≤10% traffic, then step up with monitoring and rapid rollback.
  • Document evidence: captures showing negotiated groups, dashboards, attestation pack, and change approvals.
  • Where you need extra hands on fixes or config rollout, engage our Remediation Services.

Rollout mechanics (safe & reversible)

  • Feature flag at the edge/CDN profile: “offer-hybrid-group”.
  • Canary by path or header (e.g., /pqtls/) before global.
  • Telemetry: export negotiated group (if supported) and handshake failures; at minimum, keep synthetic checks via openssl s_client running.

Real-world snippets you can copy

HAProxy with OpenSSL 3 (hybrid via providers) 

# /etc/haproxy/haproxy.cfg
global
  tune.ssl.default-dh-param 2048
  # Make OPENSSL_CONF visible to HAProxy systemd unit to load oqsprovider

frontend https_in
  bind :443 ssl crt /etc/haproxy/certs/site-ecdsa.pem alpn h2,http/1.1
  # TLS 1.3 only for pilot
  ssl-min-ver TLSv1.3
  # Cipher suites for TLS 1.3
  ssl-default-bind-ciphersuites TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256
  # Groups/Curves: controlled via OpenSSL providers (see openssl.cnf)
  default_backend app
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Systemd drop-in:

# /etc/systemd/system/haproxy.service.d/openssl.conf
[Service]
Environment=OPENSSL_CONF=/etc/ssl/openssl.cnf
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Envoy sample (classical today, hybrid when supported) 

static_resources:
  listeners:
  - name: https
    address: { socket_address: { address: 0.0.0.0, port_value: 443 } }
    filter_chains:
    - transport_socket:
        name: envoy.transport_sockets.tls
        typed_config:
          "@type": type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.DownstreamTlsContext
          common_tls_context:
            tls_params:
              tls_minimum_protocol_version: TLSv1_3
              # When your build supports it, prefer hybrid group first.
              # Some Envoy/OpenSSL combos inherit this via providers.
            tls_certificates:
            - certificate_chain: { filename: "/etc/envoy/site-ecdsa.crt" }
              private_key:       { filename: "/etc/envoy/site-ecdsa.key" }
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mTLS client (Go) with classical leafs; server may offer hybrid KEM 

cfg := &tls.Config{
    MinVersion: tls.VersionTLS13,
    Certificates: []tls.Certificate{load("client-ecdsa.pem")},
    InsecureSkipVerify: false,
    // Do not pin curves; let the stack negotiate (hybrid/classical)
}
conn, err := tls.Dial("tcp", "staging-pqtls.example.com:443", cfg)
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How we’ll validate and help you ship

  • Run your public site through our Free Website Vulnerability Scanner to verify HTTP headers and quick TLS hygiene before/after the rollout. Then track deltas as you harden configs.
  • If you want a structured start and audit-ready evidence, loop in our Risk Assessment Services. If you need extra engineering power for configs/automation, our [Remediation Services] team can co-implement and retest.

Sample Report by our tool to check Website Vulnerability:

Sample vulnerability assessment report generated with our free tool, providing insights into possible vulnerabilities.Sample vulnerability assessment report generated with our free tool, providing insights into possible vulnerabilities.

Related reading from our blog

Or browse all posts here: Cybersecurity Insights & News.

Closing Note

Appendix — quick commands you’ll likely reuse 

# Capture TLS ClientHello/ServerHello for evidence
tcpdump -i eth0 -s0 -w pqtls-rollout.pcap 'tcp port 443 and (tcp[13] & 0x18 != 0)'

# Grep for pinned curves/ciphers (anti-patterns to remove)
grep -RInE 'TLS_ECDHE_RSA_WITH_AES|ECDHE-ECDSA-AES|P-256|X25519' ./config ./src

# Curl budget smoke (repeat in CI; store as artifact)
for i in $(seq 1 10); do
  curl -s -o /dev/null -w "%{time_total}\n" https://staging-pqtls.example.com/healthz
done | awk '{sum+=$1} END {print "avg:",sum/NR}'
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