CVE-2021-31921: Critical severity istio vulnerability

Published Jun 2, 2021
·
Updated

Istio before 1.8.6 and 1.9.x before 1.9.5 contains a remotely exploitable vulnerability where an external client can access unexpected services in the cluster, bypassing authorization checks, when a gateway is configured with AUTOPASSTHROUGH routing configuration.

Affected Software

2 affected components
Istio Istio<1.8.6
Istio Istio>=1.9.0<1.9.5

Event History

Jun 2, 2021
CVE Published
via MITRE·03:36 PM
Data Sourced
via MITRE·03:36 PM
Description

Frequently Asked Questions

1

What is the vulnerability ID for this Istio vulnerability?

The vulnerability ID for this Istio vulnerability is CVE-2021-31921.

2

What is the severity of CVE-2021-31921?

The severity of CVE-2021-31921 is critical.

3

How does CVE-2021-31921 affect Istio?

CVE-2021-31921 affects Istio versions before 1.8.6 and 1.9.x before 1.9.5 where an external client can access unexpected services in the cluster, bypassing authorization checks.

4

How can an attacker exploit CVE-2021-31921?

An attacker can exploit CVE-2021-31921 by leveraging an external client to access unexpected services in the cluster without proper authorization.

5

Are there any fixes available for CVE-2021-31921?

Yes, fixes are available for CVE-2021-31921. Upgrade to Istio version 1.8.6 or higher, or 1.9.5 or higher to mitigate the vulnerability.

Contact

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