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Certificate failures can cost firms over $250,000

DigiCert survey finds certificate failures cost firms over $250,000 per incident, with 47-day TLS certificates set to multiply management workloads by 2029.

DigiCert's Certificate Management Outlook reports that 34% of companies experienced outages from expired certificates and 40% from mismanagement, with nearly one in four citing incidents costing over $250,000. The CA/Browser Forum's move to 47-day certificate lifespans by 2029 will require renewals eight times more often and 40 times as many domain validations. Over half of organizations manage more than 1,000 certificates, yet only 10% have automation in place, with budget constraints and legacy systems cited as key barriers.

Help Net Security · 2d agoIndustry

AWS Certificate Manager sets 2027 end date for email-validated certificate renewals

AWS Certificate Manager will phase out email validation for public certificates during 2027, requiring migration to DNS validation before September 30, 2027.

AWS Certificate Manager will stop offering email validation in new Regions on January 1, 2027, discontinue it for new certificate requests on March 31, 2027, and stop renewing email-validated certificates on September 30, 2027. This precedes the CA/Browser Forum's March 15, 2028 deadline ending email-based domain validation for publicly trusted certificates. AWS is updating the UpdateCertificateOptions API so customers can switch to DNS validation in place while retaining the certificate ARN, with Route 53 support for creating required CNAME records.

Help Net Security · Aug 14, 2026Advisory

AD Rights Management Service (Part 2): Extraction, Offline Decryption, and the Unrotatable Key

Huntress research shows AD RMS SLC root key is unrotatable and never expires, so its compromise permanently exposes all RMS-protected documents.

Part 2 of Huntress's AD RMS series details server-side attacks: extracting the Server Licensor Certificate (SLC) private key and performing offline decryption of protected documents. The SLC key has no expiry or rotation mechanism, with a 255-year certificate validity (2002–2258), so whoever recovers it can decrypt every document the deployment ever protected, indefinitely. The author released SharpRMS, a unified tool combining the 2016 DisARMS client-side attacks with new server-side key extraction and decryption capabilities. The research frames the SLC as comparable to KRBTGT and the DPAPI domain backup key, though not equivalent to domain compromise.

Huntress · 6d agoResearch

I've factored the RSA keys of a Certificate Authority from the 90s

Security researcher factored two 512-bit RSA root CA keys from defunct 1990s certificate authority E-Certify using CADO-NFS on a desktop in roughly 30 hours each.

A researcher extracted legacy root certificates from archived Netscape and Internet Explorer installers, identifying two 512-bit RSA roots shipped with Netscape 4.51 in 1999 by the defunct Canadian CA E-Certify. Using CADO-NFS on a Ryzen 9 5950X desktop, the keys were factored in 32 and 29 hours respectively, allowing private key reconstruction. The work comes shortly after RSA-260 (862-bit) was factored, the largest known factorization to date. The researcher also built a legacy TLS server and published keys and tools on GitHub.

CISA Shares 17 Techniques Used by Hackers to Compromise Active Directory

CISA and five international agencies publish joint guidance detailing 17 techniques attackers use to compromise Microsoft Active Directory environments.

CISA, NSA, and the Australian Signals Directorate's ACSC, with contributions from Canadian, UK, and New Zealand cyber centers, released technical guidance on 17 Active Directory attack techniques. It covers AD Domain Services, AD Certificate Services, and AD Federation Services, including Kerberoasting, DCSync, Golden Ticket, Golden SAML, Skeleton Key, and Shadow Credentials. The guidance recommends treating domain controllers, CAs, AD FS servers, and Entra Connect systems as Tier 0 assets with phishing-resistant MFA, Kerberos pre-authentication enforcement, and disabling NTLM/SMBv1.

Cyber Security News · 1d agoAdvisory

AD Rights Management Service (Part 1): Architecture, Deprecation, and Reconnaissance

Huntress maps AD RMS architecture and recon paths, setting up an offline key-extraction attack against its unrotatable 255-year root key.

Huntress's multi-part research examines Active Directory Rights Management Services, Microsoft's enterprise DRM role that still ships in Windows Server 2025 despite migration guidance favoring Azure Information Protection. Part 1 covers the trust model and how an ordinary domain account can locate RMS clusters and read rights-policy templates. Part 2 will detail four independent paths for extracting the Server Licensor Certificate (SLC) private key via service-group membership and the configuration database, enabling fully offline decryption of protected documents. The SLC certificate is valid from 2002 to 2258 and has no key-rotation mechanism, so a stolen key decrypts protected content indefinitely.

Huntress · 8d agoResearch1

Accountability in Certificate Transparency and Variants

Formal Dolev-Yao analysis shows plain Certificate Transparency requires an honest log, SCT Auditing removes that assumption, and Gossiping does not.

The paper analyzes accountability in Certificate Transparency and its SCT Auditing and Gossiping extensions in the Dolev-Yao model, starting from a vanilla PKI. It finds plain CT provides accountability only under the assumption of an honest log. The SCT Auditing extension can eliminate that assumption, while the Gossiping extension cannot. CT is supported by all major browsers and obliges Certificate Authorities to record issued certificates in public, monitored logs.

arXiv cs.CR · 6d agoResearch

Certificate Transparency Monitoring is now generally available

Cloudflare's Certificate Transparency Monitoring is now generally available, and it no longer alerts on certificates Cloudflare issued for your own domains.

Cloudflare announced general availability of its Certificate Transparency Monitoring service. The key behavioral change is that alerts are no longer generated for certificates that Cloudflare itself issued for a customer's domains, so any alert received now indicates a certificate issued by another certificate authority. Defenders can use the service to detect mis-issued or unauthorized TLS certificates for their domains.

Cloudflare Blog · Aug 13, 2026Tools