RSA‑2048 Deprecation — Why It Matters & How SafeCipher Solves It (CISO + Engineering)
Audience: CISOs, security leaders, and engineering teams who need a clear, shared plan to retire RSA‑2048 before NIST deprecation (2030) and move to ≥128‑bit and post‑quantum (PQC) cryptography without outages.
The Problem in Plain English (CISO Brief)
- Policy risk: RSA‑2048 (~112‑bit) will be deprecated by 2030 and disallowed by 2035. Audits, partners, and regulators will reject weak chains.
- Operational risk: Expired or non‑compliant certificates cause outages across apps, APIs, payments, and identity.
- Confidentiality risk: Hack‑Now‑Decrypt‑Later (HNDL)—attackers can record encrypted traffic now and decrypt it later.
- Business risk: Contract penalties, SLA breaches, and reputational damage if you miss the window.
The Problem in Technical Terms
- Algorithm strength: RSA‑2048 ≈ 112‑bit security. Target RSA‑3072/4096 or ECDSA‑P‑256/P‑384 as interim; pilot ML‑DSA (signatures) and ML‑KEM (key exchange) for PQC.
- PKI hierarchy: Roots/intermediates, OCSP/CRL signers, leaf profiles, EKUs, naming/SAN rules—all need rework.
- Ecosystems: TLS/mTLS, S/MIME, code signing, IoT/OT, VPN/SD‑WAN, Kubernetes/service mesh; clients vary widely.
- Performance: PQC artifacts are larger → plan short chains, TLS certificate compression (RFC 8879), resumption/QUIC, capacity uplift.
- Automation: Estate‑wide enrollment and rotation via ACME/EST/SCEP/CMP under a CLM control plane.
Where RSA‑2048 Breaks Things
- Public & internal TLS/mTLS — load balancers, proxies, APIs, microservices, service mesh (cert‑manager, SPIFFE/SPIRE)
- S/MIME & smart cards (PIV/CBA) — email, user auth, portals
- Code/document signing — EV/OV identities, TSA/LTV, notarisation
- IoT/OT & embedded — device bootstrap, secure boot, firmware signing, gateway mTLS
- PKI backends — Microsoft AD CS, EJBCA, Keyfactor, Venafi/CyberArk, DigiCert, Entrust
- HSM/KMS custody — Thales Luna, Entrust nShield, Azure Managed HSM, AWS CloudHSM, Google Cloud HSM
Why SafeCipher (Vendor‑Neutral, Outcome‑Driven)
- Zero‑outage migrations with blue/green issuance, canary renewals, and rollback windows
- Crypto‑agility & CLM governance (ACME/EST/SCEP/CMP) across apps, devices, and workloads
- FIPS 140‑3 HSM ceremonies with full custody evidence (M‑of‑N) and sovereignty alignment
- PQC readiness via ML‑DSA/ML‑KEM pilots, compatibility testing, and performance tuning
- Audit‑ready policy packs (Crypto Policy, Key Management Standard, CP/CPS), traceability matrices, immutable logs
Target State
- PKI hierarchy uplift: new roots/intermediates at ≥128‑bit strength; engineered short chains
- CLM control plane: policy‑as‑code; enrollment via ACME/EST/SCEP/CMP; expiry SLOs; chain drift detection
- PQC pilots: internal ML‑DSA signatures + ML‑KEM key exchange; parallel chains (classical & PQC) as support emerges
- Connectivity & performance: mTLS everywhere; certificate compression (RFC 8879); resumption/0‑RTT (where safe); QUIC/HTTP‑3
RSA‑2048 Deprecation Roadmap
Quarter 1 — Assessment & Policy (CBOM, Risk, Governance)
- CISO: risk acceptance, budget, scope, KPIs (expired‑cert incidents → zero, issuance p95/p99)
- Engineering: Cryptographic Bill of Materials (CBOM); RSA‑2048 coverage; deprecation heat‑map; draft policy (≥128‑bit, hash lifetimes, EKUs)
Quarter 2 — Architecture & Custody (Design, HSM, CLM)
- CISO: sign‑off on FIPS 140‑3 HSM model (on‑prem/cloud/hybrid), residency & lawful access
- Engineering: new intermediates, template/profile sets; CLM patterns (ACME/EST/SCEP/CMP); private links to HSMs (Direct Connect/ExpressRoute/Interconnect)
Quarter 3 — Execution Wave 1 (TLS/mTLS, Code Signing)
- CISO: production change governance, rollback authority, progress dashboard
- Engineering: blue/green issuance for edge TLS & internal mTLS; code‑signing identity uplift; cert compression enablement
Quarter 4 — Execution Wave 2 (S/MIME, IoT/OT, Legacy)
- CISO: audit evidence pack review, partner/regulator comms
- Engineering: S/MIME templates, device bootstrap refresh, compatibility islands (proxies/terminators) for legacy
Ongoing — PQC Pilot & Scale‑Out
- CISO: investment cadence; KPI trend
- Engineering: ML‑DSA/ML‑KEM pilots, QUIC/HTTP‑3 evaluation, expansion by business unit
RSA‑2048 Deprecation Deep‑Dive
RSA‑3072 vs RSA‑4096 (Bit Strength, Latency, Lifetimes)
Pick RSA‑3072 for wider compatibility and faster verifies; RSA‑4096 for long‑lived anchors. Validate handshake sizes and CPU cost.
Hybrid TLS with ML‑KEM + Classical Suites
Expose parallel endpoints; negotiate ML‑KEM where supported; keep ECDHE for others. Measure negotiation telemetry; prefer QUIC on lossy paths.
Certificate Compression (RFC 8879) & Short Chains
Enable compression (Brotli/Zstd). Keep chains Root → Intermediate → Leaf. Trim SANs and unused OIDs. Prefer short‑lived leaves to reduce revocation.
CLM Automation — ACME / EST / SCEP / CMP
Use the right protocol per estate (web/app, services, devices). Enforce maintenance‑window renewals with canary cohorts and automatic rollback.
KPIs & Evidence (Board & Audit)
- Issuance latency: p95/p99 targets
- Renewal success rate: >99% across cohorts
- Expired‑cert incidents: 0
- CRL/OCSP SLOs: availability and freshness
- Coverage: % RSA‑2048 retired, % endpoints on ≥128‑bit, pilot coverage for PQC
Platforms We Support (Vendor‑Neutral)
- PKI/CLM: Microsoft AD CS, EJBCA, Keyfactor, Venafi/CyberArk, DigiCert, Entrust
- HSM/KMS: Thales Luna, Entrust nShield, Azure Managed HSM, AWS CloudHSM, Google Cloud HSM
- Kubernetes & Service Mesh: cert‑manager, SPIFFE/SPIRE
FAQs RSA‑2048 Deprecation
Do we need to replace roots now? Introduce new ≥128‑bit or PQC‑ready roots/intermediates and phase issuance; retire legacy roots on schedule.
Will we break devices or browsers? We use parallel chains and compatibility islands until ecosystems catch up.
How do we avoid outages? Blue/green issuance, canary renewals, rollback runbooks, and CLM‑enforced policy.
Is PQC ready for the public web? Emerging. Start with internal pilots (ML‑DSA/ML‑KEM); keep classical for public until support stabilises.
Why Choose SafeCipher Now
Because the window to retire RSA‑2048 safely is closing. We bring enterprise PKI migration services, crypto‑agility & CLM governance, FIPS 140‑3 HSM ceremonies, and PQC advisory into one accountable program.