# CVE-2021-31920: Istio Authorization Bypass Vulnerability

Source: https://junglewise.ai/threats/cve-2021-31920-istio-authorization-bypass-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-05-24  
License: CC BY 4.0 with a link back

CVE-2021-31920 · Severity: low · CVSS 3.1 · Published 2022-05-24

Istio Authorization Bypass Vulnerability

Technologies: [istio.io/istio (Go)](https://junglewise.ai/threats/technologies/istio-io-istio). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2021-31920 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-31920 being exploited in the wild.

**How severe is CVE-2021-31920?** Low severity, with a CVSS score of 3.1, published 24 May 2022.

**Which products and versions are affected?** istio.io/istio (Go) SEMVER:introduced=0,fixed=1.8.6.

**Is there a fix for CVE-2021-31920?** Yes. istio.io/istio (Go): upgrade to 1.8.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2021-31920?** Check whether you run istio.io/istio (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- istio.io/istio (Go): upgrade to 1.8.6 or later

  ```sh
  go get istio.io/istio@v1.8.6
  ```


## Affected products

- istio.io/istio (Go) SEMVER:introduced=0,fixed=1.8.6

## Identifiers

- CVE-2021-31920
- GHSA-6q5m-22mq-q2xv

## Related threats

- [GO-2026-5363 - Istio: SSRF via RequestAuthentication jwksUri in istio.io/istio](https://junglewise.ai/threats/cve-2026-41413-istio-ssrf-via-requestauthentication-jwksuri)
- [Istio AuthorizationPolicy regex injection in serviceAccounts](https://junglewise.ai/threats/cve-2026-39350-istio-authorizationpolicy-regex-injection-in-serviceaccounts)
- [Ill-formed headers may lead to unexpected behavior in Istio](https://junglewise.ai/threats/cve-2022-31045-ill-formed-headers-may-lead-to-unexpected-behavior-in-istio)
- [Istio vulnerable to denial of service](https://junglewise.ai/threats/cve-2019-18817-istio-vulnerable-to-denial-of-service)
- [Istio ReDoS Vulnerability](https://junglewise.ai/threats/cve-2019-14993-istio-redos-vulnerability)