Authentication Bypass Affecting istio.io/istio/pilot/pkg/security/authz/matcher package, versions >=1.11.0 <1.11.1>=1.10.0 <1.10.4<1.9.8


Severity

Recommended
0.0
high
0
10

CVSS assessment made by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.14% (51st percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Authentication Bypass vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-GOLANG-ISTIOIOISTIOPILOTPKGSECURITYAUTHZMATCHER-1569602
  • published25 Aug 2021
  • disclosed25 Aug 2021
  • creditYangmin Zhu of Google

Introduced: 25 Aug 2021

CVE-2021-39156  (opens in a new tab)
CWE-287  (opens in a new tab)

How to fix?

Upgrade istio.io/istio/pilot/pkg/security/authz/matcher to version 1.11.1, 1.10.4, 1.9.8 or higher.

Overview

istio.io/istio/pilot/pkg/security/authz/matcher is an An open platform to connect, manage, and secure microservices.

Affected versions of this package are vulnerable to Authentication Bypass. An HTTP request with a fragment in the URI path (a section in the URI that begins with a # character) could bypass Istio’s URI path-based authorization policies. For instance, an Istio authorization policy may deny requests sent to the URI path /user/profile. In the vulnerable versions, a request with URI path /user/profile#section1 bypasses the deny policy and routes to the backend (with the normalized URI path /user/profile%23section1), possibly leading to a security incident.

You are impacted by this vulnerability if you use authorization policies with DENY actions and operation.paths, or ALLOW actions and operation.notPaths.

The fix depends on a fix in Envoy, which is associated with CVE-2021-32779.

CVSS Scores

version 3.1