certsecure.chTested, practical guides on public key infrastructure — certificates, CAs, TLS and the standards that hold them together.https://certsecure.ch/enAdvisory: Chain Validation Bypass in Common TLS Stackshttps://certsecure.ch/guides/cve/https://certsecure.ch/guides/cve/A name-constraint parsing flaw lets a crafted intermediate assert authority it was never granted. Affected versions and fixes inside.Wed, 05 Aug 2026 00:00:00 GMTAdvisoriesAdvisoriesTLS/SSLVulnerabilityCertificate Revocation: CRL vs OCSP vs Staplinghttps://certsecure.ch/guides/revocation/https://certsecure.ch/guides/revocation/Revocation is where most PKI deployments quietly fall apart. Here is how each mechanism works and which one to actually rely on.Tue, 04 Aug 2026 00:00:00 GMTKey ManagementKey ManagementRevocationOCSPTLS/SSLHow X.509 Certificates Actually Workhttps://certsecure.ch/guides/x509/https://certsecure.ch/guides/x509/A field guide to the certificate you stare at every day: fields, extensions, the chain, and what a validator is really checking.Tue, 28 Jul 2026 00:00:00 GMTPKI BasicsPKI BasicsX.509CertificatesBuilding a Two-Tier CA Hierarchy with OpenSSLhttps://certsecure.ch/guides/twotier/https://certsecure.ch/guides/twotier/Stand up an offline root and an issuing intermediate from scratch, with sane extensions, CRL and OCSP endpoints wired in.Tue, 21 Jul 2026 00:00:00 GMTTutorialsTutorialsCertificate AuthorityOpenSSLACME and Fully Automated Certificate Managementhttps://certsecure.ch/guides/acme/https://certsecure.ch/guides/acme/How the ACME protocol issues, renews and revokes certificates without a human in the loop, and where automation still bites.Wed, 15 Jul 2026 00:00:00 GMTTutorialsTutorialsACMEAutomationPost-Quantum Cryptography: Preparing Your PKIhttps://certsecure.ch/guides/pqc/https://certsecure.ch/guides/pqc/Hybrid certificates, crypto-agility and the migration timeline. What to inventory now before the standards land in production.Thu, 09 Jul 2026 00:00:00 GMTStandardsStandardsPost-QuantumMigrationCertificate Transparency Logs, Explainedhttps://certsecure.ch/guides/ct/https://certsecure.ch/guides/ct/What SCTs are, why browsers demand them, and how CT turns misissuance from a secret into a public, auditable record.Tue, 30 Jun 2026 00:00:00 GMTStandardsStandardsCertificate TransparencyAuditingChoosing Key Sizes and Algorithms in 2026https://certsecure.ch/guides/keysize/https://certsecure.ch/guides/keysize/RSA-3072, ECDSA P-256 or Ed25519? A practical decision guide for what to deploy today and what to avoid.Wed, 24 Jun 2026 00:00:00 GMTKey ManagementKey ManagementAlgorithmsBest Practices