Microsoft emergency updates block compromised eMudhra certificates
Original title: Microsoft Releases Emergency Windows Updates to Block Compromised eMudhra Certificates
Eight recoverable intermediate keys could forge TLS or code-signing certificates; Microsoft says its own systems were not affected.
Microsoft released emergency Windows trust updates after finding eight recoverable eMudhra intermediate CA private keys. Six relate to TLS and two to code signing, which could let an attacker impersonate a site or sign software as a trusted publisher. An October 26 out-of-band Windows update removes seven certificates, and Microsoft said on October 27 that Edge’s trust list was updated as well. Microsoft says these are potential uses, not proof that such attacks occurred.
Unconfirmed: Microsoft describes possible misuse of the keys and does not say those attacks have occurred.
- Windows first blocked the authorities through the Disallowed Certificate Trust List on October 20.
- A CRLSet update blocks affected TLS certificates in Edge and WebView2 without a new browser version.
- The later removal covers six eMudhra G3 roots and an AAA Certificate Services cross-sign.
- That removal is separate from blocking the eight intermediate keys and from eMudhra’s revocations.
- Disconnected Windows systems and Azure virtual machines need an alternate update path.
Impact: Forged TLS or code-signing certificates if recovered keys are misused
| Product | Affected | Fixed in |
|---|---|---|
| eMudhra intermediate CA certificates | eight recoverable intermediate private keys | — |
| Microsoft Windows certificate trust list | — | October 26 out-of-band update |
- 1.Allow Windows certificate trust updates and Edge component updates to reach managed devices.
- 2.Do not locally restore trust in the removed certificates without assessing the risk.
- 3.Replace certificate chains that depend on the seven removed certificates.
- Products
- WindowsMicrosoft EdgeWebView2
From the original article
2 min read at cybersecuritynews.com
Microsoft released emergency Windows trust updates after discovering eight recoverable eMudhra intermediate CA private keys that could let attackers forge trusted certificates or sign malicious content. Microsoft said the issue affected eMudhra’s certificate hierarchy, not Microsoft systems. The response includes an October 26 out-of-band Windows update removing seven certificates from the Windows trust list.
By Abinaya · cybersecuritynews.com
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