CVE-2026-111943 and CVE-2026-111944: Eight eMudhra intermediate CA certificates carry fatally weak P-384 keys, enabling private-key recovery and fraudulent cert issuance. Chrome, Mozilla, Apple, and Microsoft have blocked them; your environment may still trust them. Key findings: - The root cause is a flaw in a key generation ceremony held April 30, 2025, for 24 subordinate CAs. A wrap/unwrap step produced a second set of weak P-384 keys, reducing effective entropy to an estimated 3 to 8 bits, making private-key recovery trivial to compute. Six of the eight affected intermediates are TLS CAs; two are code-signing CAs. Google removed emSign ECC Root CA - G3 from the Chrome Root Store entirely. eMudhra states its root CA private keys and other intermediates are not affected, and that no leaf certificates were issued to websites or end users under the compromised intermediates. - The eight affected intermediates span eMudhra BV (G3B) and eMudhra Inc (G3C) and cover EV/OV/DV TLS and OV code-signing roles. Reliable identifiers for each are their SHA-256 fingerprints and serial numbers, all listed in the report. Example: EM EV TLS CA - G3B carries serial c7c41efe92d825f05eae841a4a82c1 and fingerprint E7568FE6E12331F4FD7DE61DA4C7559D0F8EB192A218D4741A3BA75184333838. - Go runtimes are a distinct exposure path. Go 1.27.3 and 1.26.10 block chains containing the compromised keys under CVE-2026-111943. Older Go versions will still accept those chains. The report notes that unmanaged endpoints and custom trust stores that do not receive automatic distrust updates remain at risk regardless of browser-level blocks. - Revocation is not a complete control. eMudhra has revoked all eight intermediates, but clients that skip revocation checks can still accept a chain containing them. Confirming that CRL and OCSP checks are functioning correctly is a required response step, not optional hygiene. Hunt. The issuer-organization query is certificate:(issuer.organization:eMudhra BV or issuer.organization:eMudhra Inc) and the serial-number query targets all eight compromised intermediates individually. For Go runtime exposure, the report ties QID 5019897 to affected Go versions. For certificate chain enumeration on hosts, QID 48395 (eMudhra Intermediate CA Certificates Enumeration) covers assets presenting or using chains containing the compromised intermediates. Any leaf certificate whose chain includes one of the eight should be reissued by a different trusted CA and redeployed before trusting revocation status alone to protect users. The eight SHA-256 fingerprints and serial numbers are in the report. #DFIR_Radar
