--- title: "Post-Quantum Cryptography" description: "8 posts about Post-Quantum Cryptography, summarised, each linking to the original." --- # Post-Quantum Cryptography > 8 posts about Post-Quantum Cryptography, summarised, each linking to the original. ## Articles ### [Everything we launched during Birthday Week 2026](https://yomu.fyi/post/everything-we-launched-during-birthday-week-2026.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Meagan Gamache - Published: Oct 5, 2026 - Type: Announcement Cloudflare marked its 16th Birthday Week with 46 announcements spanning open source, application security, AI agent economics, and developer platform upgrades. The week began with a new agentic CLI called cf, an open-source generation pipeline called Forge, and EmDash, a serverless CMS with sandboxed plugins. Tuesday focused on Cloudflare’s intention to become a public certificate authority and post-quantum security tools. Wednesday introduced Pay Per Use and the Monetization Gateway, creating an economic model for AI agents to pay creators when using their content. The week closed with features for faster connectivity and broader accessibility. ### [Support for modern cryptographic algorithms in Workers](https://yomu.fyi/post/support-for-modern-cryptographic-algorithms-in-workers.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Thibault Meunier - Published: Oct 1, 2026 - Type: Announcement Cloudflare Workers now provides opt-in support for post-quantum cryptographic algorithms ML-KEM and ML-DSA within the Web Crypto API, including ML-KEM-768, ML-KEM-1024, ML-DSA-44, ML-DSA-65, and ML-DSA-87. These algorithms enable key encapsulation via encapsulateBits and decapsulateBits, and signatures via sign and verify, along with helper APIs like getPublicKey and SubtleCrypto.supports for feature detection. The implementation is gated behind the webcrypto\_modern\_algorithms compatibility flag and is based on a draft WICG specification, meaning it is opt-in while the specification is still moving. Developers can now use native primitives instead of bundling separate cryptographic code, reducing application size and maintenance burden for developers. Libraries such as panva/jose for JWTs and panva/hpke for HPKE can delegate ML-KEM and ML-DSA to the runtime, enabling experimentation with post-quantum protocols and preparing for the migration. ### [Using AI to chart a course for our post-quantum migration](https://yomu.fyi/post/using-ai-to-chart-a-course-for-our-post-quantum-migration.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Tiago Silva - Published: Sep 29, 2026 - Type: Explainer Cloudflare is racing toward a 2029 deadline for full post-quantum readiness, having already upgraded many products to post-quantum encryption but still needing to address authentication and remaining classical cryptography. To manage this massive migration, they built CryptoLabe, an internal AI-powered tool that scans their centralized codebase to discover and classify cryptography usage. The tool operates in two stages: discovery finds raw observations of cryptography across source, configuration, manifests, lockfiles, scripts, tests, and documentation, then analysis re-checks each observation, investigates runtime use and dependencies, and assigns classifications such as classical encryption, signature, or token. CryptoLabe also surfaces prerequisites where PQ migration is blocked by missing standards or library support, enabling Cloudflare to work with standards bodies and ecosystem stakeholders to drive migration plans. The post shares learnings for other organizations, recommending starting with a single repository, validating results, and prioritizing high-impact systems. ### [Building a certificate authority for the whole Internet](https://yomu.fyi/post/building-a-certificate-authority-for-the-whole-internet.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Steve Goldsmith - Published: Sep 29, 2026 - Type: Announcement Cloudflare, which terminates TLS for millions of domains and sits in front of over 20% of global Internet request traffic, announced its intent to become a public certificate authority (CA) during Birthday Week 2026. The company has applied for inclusion in the Chrome, Apple, Microsoft, and Mozilla root programs and signed a definitive agreement to acquire an established root from GlobalSign. This acquisition ensures certificate compatibility with older clients that a fresh root would never reach, addressing the long tail of devices where avoidable breakage occurs. Cloudflare plans to be among the first CAs to issue production Merkle Tree Certificates (MTCs) in early 2027, targeting post-quantum readiness as part of Chrome’s Quantum-resistant Root Program. The CA will be ACME-first, require ACME Renewal Information (ARI) support for issuance, and operate transparently with reproducible builds of signing software and a public dashboard. ### [Building a post-quantum certificate authority with Merkle Tree Certificates](https://yomu.fyi/post/building-a-post-quantum-certificate-authority-with-merkle-tree-certifi.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Mari Galicer - Published: Sep 29, 2026 - Type: Announcement The Web PKI faces a scaling problem because post-quantum (PQ) signatures are roughly 40 times larger than classical ones, making direct adoption at Internet scale expensive. Merkle Tree Certificates (MTCs) address this by batching certificates into an append-only Merkle tree, allowing a CA to sign the tree root and clients to verify with a compact inclusion proof. Cloudflare is building a certificate authority that will support MTC issuance, targeting early 2027 for inclusion in Chrome’s new Quantum-resistant Root Store, and will offer standard MTC issuance at no cost. The MTC architecture couples issuance with logging (“issue by logging”), making transparency a first-party property rather than an add-on, which reduces redundancy and scaling overhead. Cloudflare successfully completed an experimental deployment with Chrome and is now moving to full production, but notes that broader ecosystem participation from browsers, CAs, and monitors is needed for the transition. ### [Is your domain using post-quantum encryption? Now you can see for yourself](https://yomu.fyi/post/is-your-domain-using-post-quantum-encryption-now-you-can-see-for-yours.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Sharon Goldberg - Published: Sep 29, 2026 - Type: Announcement Cloudflare introduced new post-quantum cryptography visibility tools in its Application Security and Logs products, including Logpush, Log Explorer, and the HTTP Traffic Analytics dashboard, to help customers monitor encryption adoption. These tools surface the key exchange algorithm negotiated on every incoming request, enabling customers to audit their post-quantum posture, assess compliance, and identify cryptographic gaps across their domains. The primary post-quantum algorithm in TLS 1.3 is X25519MLKEM768, a hybrid of classical ECDHE over curve X25519 and the post-quantum ML-KEM, which provides belt-and-suspenders security against harvest-now-decrypt-later attacks. Cloudflare Radar data shows about 70% of browser-generated traffic uses post-quantum encryption on the visitor-to-Cloudflare connection, but only 15% of origin connections to Cloudflare use hybrid ML-KEM. For legacy origin servers that cannot support modern post-quantum cryptography, Cloudflare Tunnel can tunnel traffic over TLS 1.3 with X25519MLKEM768 without requiring any upgrade to the origin server itself. ### [Preventing quantum downgrade attacks against IPsec](https://yomu.fyi/post/preventing-quantum-downgrade-attacks-against-ipsec.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Lina Baquero - Published: Sep 29, 2026 - Type: Announcement Cloudflare has identified a design flaw in IPsec that allows a quantum attacker to downgrade post-quantum-protected connections to classical cryptography. The attack exploits the fact that IKEv2 endpoints sign only their outbound messages rather than the full handshake transcript. This vulnerability requires a quantum computation in real time during the handshake, and resource estimates for such attacks have decreased, prompting Cloudflare to move its transition deadline to 2029. To mitigate this, Cloudflare worked with the IETF to develop a full transcript authentication extension for IKEv2 that prevents downgrade attacks. The extension is now available in beta for Cloudflare WAN and Magic Transit customers on an opt-in basis. ### [1.1.1.1 now supports post-quantum DNSSEC, all 2,420 bytes of it](https://yomu.fyi/post/1-1-1-1-now-supports-post-quantum-dnssec-all-2-420-bytes-of-it.md) - Company: [Cloudflare](https://yomu.fyi/company/cloudflare.md) - Author: Sebastiaan Neuteboom - Published: Sep 10, 2026 - Type: Announcement 1.1.1.1 now validates DNSSEC signatures made with ML-DSA-44, a NIST-standardized post-quantum algorithm, as an initial step toward post-quantum DNSSEC. The operational problem is that each signature is 2,420 bytes—almost 38 times an ECDSA P-256 signature and larger than common DNS-over-UDP limits—while zones must continue publishing conventional signatures for older resolvers. Cloudflare’s resolver handles this by testing larger responses at Internet scale, relying on truncation and transport retries rather than fragmented UDP, and using authenticated DS records to require a valid post-quantum path when a zone advertises one, preventing downgrade to conventional validation. The change provides operational experience for an ecosystem migration that requires coordination across DNS participants; Cloudflare says it plans full post-quantum security by 2029.