Compromised eMudhra intermediate certificates

Cisco Talos has flagged a serious key-generation flaw at certificate authority eMudhra, where eight intermediate CA certificates ended up with private keys containing only single- or double-digit bits of entropy instead of the required 384 bits of P-384 randomness. The mistake, traced back to an April 30, 2025 key ceremony under eMudhra's emSign Root TLS CA - G3 (cross-signed with Comodo AAA Certificate Services), effectively made the private keys trivial to recover, letting anyone who obtains them forge certificates and impersonate websites or sign malicious code. Six of the affected TLS certificates have already been distrusted by Chrome, Mozilla, and Apple, while two code-signing certificates were blocked by Microsoft, and eMudhra has revoked all eight and paused new issuance under the G3 root. Because Go's standard library performs its own certificate chain validation independently of OS trust stores, the Go team assigned CVE-2026-111943 to this exposure and shipped Go 1.27.3 and 1.26.10, which now reject chains built on the affected SPKI hashes—critical for container and cloud-native tools like Docker, Kubernetes, Terraform, and Prometheus that rely on Go's TLS stack. Talos warns that beyond browsers, VPN clients, CI/CD pipelines, and embedded or industrial IoT devices using separate or bundled trust stores may still trust the compromised keys, and urges organizations to update affected software and certificate stores as fixes roll out; no active exploitation has been observed as of October 21, 2026.