CVE-2021-31920 affects Istio, a component used by Cloud Run for Anthos

## Security [CVE-2021-31920](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-31920) affects Istio, a component used by Cloud Run for Anthos. The CVE specifically impacts Istio's path-based AuthorizationPolicy configurations. To ensure that your Cloud Run for Anthos clusters are not affected by the CVE, see the [security best practices guide](https://cloud.google.com/anthos/run/docs/securing/best-practices) to learn more about mitigating this vulnerability.