Compromise of eMudhra Root and Intermediate Certificate Authorities

# Compromise of eMudhra Root and Intermediate Certificate Authorities

https://gcdradar.vercel.app/incidents/compromise-of-emudhra-root-and-intermediate-certificate-auth · AIR-2026-1552 · live

- Lane: Patch now
- Severity: 3 (Confirmed exploitation): Critical security compromise involving Certificate Authorities.
- Fix status: Partly patched
- First reported: 2026-10-26
- AI role: No AI role
- Products: eMudhra Intermediate Certificates

## Summary

Private keys for eight eMudhra intermediate certificates were found to be critically broken due to key generation ceremony errors. Attackers can brute-force acquire these private keys within seconds.

## What to do

Apply the out-of-band Windows updates to remove trust in affected eMudhra certificates.

## Affected and fixed versions

- Affected: eMudhra intermediate certificates

## Latest updates

- 2026-10-27: Microsoft releases out-of-band Windows updates to distrust compromised eMudhra certificates (https://bleepingcomputer.com/news/microsoft/microsoft-releases-windows-oob-updates-to-distrust-emudhra-certificates)
- 2026-10-26: Cisco Informational for Emergency Distrust of eMudhra Root and Intermediate Certificate Authorities (https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-emudhra-info-ScS22A1r?vs_f=Cisco+Security+Advisory%26vs_cat%3DSecurity+Intelligence%26vs_type%3DRSS%26vs_p%3DCisco+Informational+for+Emergency+Distrust+of+eMudhra+Root+and+Intermediate+Certificate+Authorities%26vs_k%3D1)

## Sources

- 2026-10-26 Cisco: Cisco Informational for Emergency Distrust of eMudhra Root and Intermediate Certificate Authorities https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-emudhra-info-ScS22A1r?vs_f=Cisco+Security+Advisory%26vs_cat%3DSecurity+Intelligence%26vs_type%3DRSS%26vs_p%3DCisco+Informational+for+Emergency+Distrust+of+eMudhra+Root+and+Intermediate+Certificate+Authorities%26vs_k%3D1
- 2026-10-27 BleepingComputer: Microsoft releases Windows OOB updates to distrust eMudhra certificates https://bleepingcomputer.com/news/microsoft/microsoft-releases-windows-oob-updates-to-distrust-emudhra-certificates

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.