CA/PKI Weekly Digest - Sep 21 - Sep 28, 2026

Last week SSL.com reported that they revoked 2,700 website certificates in a matter of couple hours because they failed to perform all required procedures on 6,031 certificates since March 2025. The issue was discovered by the external audit, details here bug 2071491.

Earlier this year SSL.com had a similar problem bug 2029230 in April. Same external audit also found six root certificates bought from VikingCloud, missing from SSL.com's public repository (bug 2074980).

Unfortunately as a customer, there is no way to know that your CA failed to meet all of their internal procedures, but TLS Radar could have helped detect the revoked certificate within minutes after it happened. Revoked certificate stops working without warning: browsers that check revocation show visitors a full-page security warning instead of opening the website. There is no way to stop a CA from revoking your certificate and it’s not clear if SSL.com notified their customers in advance but TLS Radar's revocation monitoring* would have emailed you as soon as a scan discovered the revocation, giving you an early signal to replace it.

eMudhra promised one key size in its rules and issued several others (bug 2073581).

Sectigo's published rules said its website certificates contain both of two usage settings - server and client authentication, and some of its certificates have only one. Sectigo agrees the sentence was unclear, says it meant its certificates as a group, has rewritten it, and will not revoke anything. It is tracking every certificate issued under that wording in bug 2069640: 96.6 million still active on September 21. The bug does not say how many of them are actually missing the setting. In August the Chrome Root Program said it has "a really hard time" reading "both X and Y" as anything but both. None of the browser representatives have commented in either of Sectigo's incident bugs yet.

A deadline also caught out four CAs. Old intermediate certificates signed with SHA-1 had to be revoked by September 15. GoDaddy revoked its two on September 17 (bug 2072663). DigiCert revoked two (bug 2073668). FNMT revoked its one on September 21 (bug 2073233). Firmaprofesional had still not revoked its one by September 23, because timestamping services still rely on it (bug 2072600). In all four cases, someone from the outside pointed out the miss. TLS Radar flags revoked intermediates so customers are aware of this.

Revocation lists had a bad week too. Browsers and other software learn which certificates have been cancelled by looking up these lists (aka CRLs). On September 23, reports of broken lists reached at least four CAs at once. Certum had an encoding error in 15 lists (bug 2075242). Telia signed its lists with the wrong algorithm (bug 2075488). KIR set one list to last 300 seconds longer than the 12 months allowed (bug 2075606). Actalis listed 149 revocations dated January 1970 (bug 2075655). SHECA, NETLOCK and Disig reported similar problems by Saturday, and Let's Encrypt found missing details in two of its lists (bug 2074944). Telia admitted its own checking tools missed both of its problems.

Among many other things TLS Radar also monitors broken revocation services, catches lists that are out of date, badly signed, unreadable or missing, like DigiCert's stale list from September 17.

* Revocation monitoring is available on Business and Enterprise plans

A weekly summary of certificate authority incidents and compliance activity, sourced from Mozilla's public CA Program tracker.

New this week

• DigiCert: Revocation of Undisclosed Issuing CAs - source
• Actalis: Incorrect Revocation dates in CRL entries - source
• Telekom Security: Failure to respond to a certificate problem report within 24 hours - source
• Telekom Security / DFN: crlEntryExtensions SEQUENCE of size 0 - source
• Disig: CRL contains not allowed attributes - source
• SHECA: ECC CRL/OCSP Signature Algorithm Issue - source
• Kamu SM: Missing CRL Disclosure for Cross-Signed CA in CCADB - source
• NAVER Cloud Trust Services: Missing CRL disclosure for two subordinate CAs in CCADB - source
• NETLOCK: Certificate Problem Report [CRL RFC 5280 S5.2.3] - source
• KIR: SZAFIR ROOT CA3 TLS CRL nextUpdate exceeds 12 months - source
• Firmaprofesional: certificateHold reasonCode entries in AC Firmaprofesional - CUALIFICADOS CRL - source
• Amazon Trust Services: CP/CPS for externally operated subordinate CAs not updated in CCADB within 14 days - source
• NETLOCK: Certificate Problem Report [CRL URL not disclosed in CCADB] - source
• NETLOCK: Certificate Problem Report [CRL BR S7.2.2] - source
• Telia: CRL signature algorithm property non-conformance for EC issuer key - source
• SwissSign - Backdating of 48+h - source
• Asseco DS / Certum: Incorrect ECDSA-SHA384 AlgorithmIdentifier Encoding in CRLs - source
• Asseco DS / Certum: CRL URLs in issued certificates not disclosed in CCADB - source
• SSL.com: Failure to Post all Root and Intermediate CA certificates in Repository identified in CP/CPS - source
• Let's Encrypt: Root CRLs Missing Reason Code - source
• DigiCert: EV JOI match with organizationIdentifer - source

Updates on open incidents

• ACCV: Delayed revocation related to Bugzilla #2061746 - source
• SwissSign: Delayed revocation related to Bugzilla 2033000 - source
• Microsec: Insufficent support for "unspecified (0)" revocation reason - source
• Firmaprofesional: Delayed revocation of SHA-1-signed AC Firmaprofesional - CA1 - source
• Sectigo: No revocation after CP/CPS language involving extendedKeyUsage found to be subject to multiple interpretations - source
• Let's Encrypt: CRLs Temporarily Missing Revoked Serials - source
• FNMT: Delayed Revocation of SHA-1 Signed Subordinate CA Certificate - source
• D-TRUST: Incomplete Disclosure of CRL URLs - source
• Firmaprofesional: OCSP signature verification errors for Secure Web 2024 certificates - source
• ACCV: Issuance of Server TLS Certificates with CP/CPS Discrepancies - source
• PKIoverheid: TSP KPN Delayed publication of audit attestation letters in the CCADB - source
• Firmaprofesional: Delayed preliminary CPR response due to incomplete mailbox monitoring coverage - source
• SSL.com: MPIC not performed for specific DCV path - source
• Microsoft PKI Services: Third-Party Code Signing CPS missed annual update and four Issuing CAs - source
• Microsoft PKI Services: Missed Seven-Day Update for Bugzilla 2059818 - source
• Actalis: failure to timely update CP/CPS for AgID SubCAs - source
• Sectigo: CP/CPS language involving extendedKeyUsage found to be subject to multiple interpretations - source
• Asseco DS / Certum: Multi-purpose Subordinate CA with missing EKU - source
• Disig: Multi-purpose Subordinate CA with missing EKU - source
• CFCA: Incorrect countryName values in OV subscriber certificates - source
• SECOM: Missing Prior Notification and Approval for a Cross-Certificate Extending Trust to Externally-Operated JPRS CAs - source
• SECOM: Five Subordinate CA Certificates Issued Without Apple Prior Approval for Cybertrust Japan (CTJ) - source
• GoDaddy: CCADB Missing Partitioned CRL URL Disclosure - source
• Firmaprofesional: Chrome Root Progam Policy - Dedicated TLS hierarchy / EKU requirements - source
• Asseco DS / Certum: EV TLS Certificate Issued with Branch Name as Subject Organization Name - source
• eMudhra emSign PKI Services: InCommon IGTF SSL CPS missing conformance statement for Baseline Requirements - source
• eMudhra emSign PKI Services: InCommon RSA IGTF Server CA 4 — certificates issued with key sizes not permitted by CPS - source
• eMudhra emSign PKI Services: Test Website TLS Certificates Issued Against CP/CPS. - source
• Chunghwa Telcom: Delay of 2025 WebTrust for CA Audit Reports seals for ePKI & HiPKI - source
• DigiCert: Expired CRL - source
• IdenTrust: Delayed disclosure of Intermediate CA in CCADB - source
• NETLOCK: Failure to Respond to a Certificate Problem Report Within 24 Hours - source
• CFCA: Cross-signed certificate missing the Extended Key Usage (EKU) extension - source
• Netlock: CA in AIA in PEM format - source
• SHECA: Disclosure alerts indicating audit information missing for 2 Sub-CAs - source
• SHECA: Failed to provide a preliminary incident report within 72 hours - source
• NETLOCK: OCSP Service Returning Error for Issued Certificate - source
• NETLOCK: Failure to file a preliminary incident report within 72 hours (OCSP responder incident, Bug 2051459) - source
• Actalis: Incorrect CRL Distribution Point in TLS Server Certificates - source
• Actalis: Issuance of Server TLS Certificates with id-kp-clientAuth against CPS - source
• Actalis: Undisclosed Subordinate CA Certificate - source
• Sectigo: Issuance of certificates including a Subject:countryName not corresponding to a Country - source
• SwissSign: Invalid Entry in State field - source
• SHECA: CP/CPS lacks explicit adherence statement - source
• Asseco DS / Certum: Incorrect Country in certificate - source
• SSL.com: Invalid Subject stateOrProvince Values - source
• Exploring the interaction between descriptive and normative language in CP/CPS documents and the potential for confusion - source
• Sectigo: jurisdictionCountry versus organizationIdentifier mismatch in QWAC - source
• DigiCert: OCSP returns unauthorized for an issued TLS Certificate - source

Resolved this week

• CFCA: Delayed response to CPR related with bug 2058918 - source
• IdenTrust: 2026 Audit Report Finding - source
• SDAIA: Missing S/MIME WebTrust audit coverage - source
• TWCA: CPR subject.countryName - source
• Amazon Trust Services: CP/CPS missing explicit adherence to latest version of policies - source
• SECOM: Inaccurate CP/CPS description regarding the basicConstraints extension of OCSP responder certificates by Cybertrust Japan (CTJ) - source
• DigiCert: CPR subject.countryName - source