Expired Certificates Cost Firms Over $250K, DigiCert Warns
A new DigiCert report finds certificate failures now cost firms over $250,000, with 34% already hit by an expired-cert outage. Here is why that matters to you.
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Certificate Bugs Behind Microsoft's 67-Hour M365 Outage
Certificate bugs, not a forgotten renewal, caused Microsoft's 67-hour Microsoft 365 outage in August 2026. Here's what the post-incident report means for you.
Exchange Online Outage Tied to an Expired Certificate
A Microsoft 365 outage on August 31, 2026 broke Outlook and Exchange Online logins for hours. Leaked error logs point to an expired certificate as the cause.
HARICA Revoked 235,301 TLS Certificates in Five Days
HARICA's incident report shows 235,301 live TLS certificates revoked in five days over a policy mismatch. Here's why revocation now beats expiry as a risk.
HARICA Revokes TLS Certs Twice in a Week Over CP/CPS Bug
HARICA revoked TLS certificates twice in ten days after CP/CPS policy violations, forcing European university networks to scramble before each tight deadline.
Microsoft Secure Boot Certificates: What IT Teams Need to Do
Microsoft Secure Boot certificates have expired. Learn how IT teams can verify updates, avoid BitLocker recovery issues, and meet the October deadline.
HARICA Won't Revoke Certs for Sanctioned Russian Banks
HARICA refused to revoke TLS certificates it issued to EU-sanctioned banks like Sberbank and VTB, testing sanctions compliance. Here's why it matters to you.
Exchange Online Now Blocks TLS 1.0 and 1.1
Microsoft started blocking TLS 1.0 and 1.1 for POP and IMAP connections to Exchange Online in July 2026. If your email client stopped connecting, here's why.
Cloudflare's TLS Bug Hit Twice in One Week
A recurring Let's Encrypt CA bundle bug broke TLS handshakes on Cloudflare twice in seven days, leaving some sites unreachable. Here's what went wrong.
Microsoft Secure Boot Certs Expire June 24
Microsoft's 2011 Secure Boot certificates start expiring June 24, 2026. Devices that miss the update lose future boot-level security patches. Here's what to check.
DigiCert Revoked G2/G3 ICAs: Is Your Site Affected?
DigiCert revoked multipurpose G2 and G3 intermediate CAs on May 15, 2026 to meet Chrome's dedicated TLS hierarchy rules. Check if your certs are affected.
Let's Encrypt Halted Issuance Over Broken Cross-Sign
Let's Encrypt stopped all certificate issuance on May 8 after a cross-sign flaw in its new Generation Y root. The postmortem reveals missing EKU fields.
DigiCert Breached via Screensaver, Certs Signed Malware
Attackers breached DigiCert's support portal with a disguised .scr file, stole EV code signing certs, and signed Zhong Stealer malware. Here's what happened.
Let's Encrypt Moves to 45-Day Certificates on May 13
On May 13, 2026, Let's Encrypt will begin issuing 45-day certificates, forcing automation for all users. Here's what you need to do to prepare.
APNIC: Why SSL Certificate Revocation Is Still Broken
APNIC's April 2026 analysis shows certificate revocation (OCSP/CRL) remains fundamentally broken. Shorter-lived certificates are the real fix — here's why.
Public mTLS Certs End May 1: Your Migration Guide
Sectigo and DigiCert stop issuing public TLS certs with clientAuth EKU on May 1, 2026. Chrome enforces June 15. Here's how to migrate before your mTLS breaks.
Critical wolfSSL Flaw Lets Attackers Forge TLS Certificates
A critical wolfSSL bug (CVE-2026-5194) lets attackers forge TLS certificates accepted by 5 billion devices. wolfSSL 5.9.1 fixes it — here's what to do now.
October 2026: The First 200-Day SSL Cert Expiration Wave
Experts warn October 1, 2026 could trigger widespread outages as the first 200-day SSL certificates expire. Research shows 40% of enterprises aren't ready.
DigiCert G1 Root CA Distrust: Act Before April 15
Chrome and Firefox distrust DigiCert's G1 root CA on April 15, 2026. Azure, Oracle, and others are already migrating. Here's what your organization must do.
Sectigo Signing Delays Hit Namecheap SSL Customers
Sectigo's signing servers went down on March 22, stalling SSL issuance for Namecheap users. As 200-day certs double renewal demand, CAs face new pressure.
Cisco Duo CA Expiry: Update Required by March 31
Cisco Duo's CA bundle expires March 31, 2026. Organizations using Duo MFA risk complete authentication lockouts if they don't update their software now.
Expired SSL Certificate Took Down Google Bazel for 13 Hours
An expired SSL certificate caused a 13-hour Google Bazel outage in December 2025. With 200-day certs starting March 15, 2026, here's why this matters to you.
Cloudflare 1.1.1.1 Certificate Scare: Unauthorized Issuance
Learn how unauthorized SSL certificate issuance for Cloudflare's 1.1.1.1 was detected via SSLboard, highlighting challenges in reporting security vulnerabilities.
No False Alerts: How SSLboard Ensures SSLcalendar Accuracy
Learn how SSLboard powers SSLcalendar with zero false positives, distinguishing used certificates via Certificate Transparency monitoring.
Public TLS Client Certificates: Sunset on June 15, 2026
Learn about the deprecation of public TLS client certificates. Chrome stops trusting them June 15, 2026—discover alternative authentication methods.
The Path to 47 Days: SSL Certificate Lifetimes Are Shrinking
Explore the timeline reducing SSL/TLS certificate validity from 398 days to 47 days by 2029, enhancing web security through shorter lifespans.
SSL Calendar Launch: The Perfect Tool for Certificate Tracking
Discover SSL Calendar, which uses familiar calendar interfaces to track SSL certificate expirations, combating tool fatigue with intuitive monitoring.