CVE-2021-31921 Missing authorization in n/a
Attackers can bypass authorization checks to access unexpected cluster services when AUTO_PASSTHROUGH routing is configured.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-31921?
CVE-2021-31921 is a critical missing authorization vulnerability in n/a, published on 2 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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 AUTO_PASSTHROUGH routing configuration.
Weakness: CWE-862
Which versions are affected by CVE-2021-31921?
It affects 1 product.
Linux distribution packages (15)
servicemesh Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-citadel Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-galley Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-istioctl Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-mixc Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-mixs Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-pilot-agent Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-pilot-discovery Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh-sidecar-injector Red Hat:service_mesh:1.1::el8 | All versions | 0:1.1.15-4.el8 |
servicemesh Red Hat:service_mesh:2.0::el8 | All versions | 0:2.0.5-3.el8 |
servicemesh-istioctl Red Hat:service_mesh:2.0::el8 | All versions | 0:2.0.5-3.el8 |
servicemesh-mixc Red Hat:service_mesh:2.0::el8 | All versions | 0:2.0.5-3.el8 |
servicemesh-mixs Red Hat:service_mesh:2.0::el8 | All versions | 0:2.0.5-3.el8 |
servicemesh-pilot-agent Red Hat:service_mesh:2.0::el8 | All versions | 0:2.0.5-3.el8 |
servicemesh-pilot-discovery Red Hat:service_mesh:2.0::el8 | All versions | 0:2.0.5-3.el8 |
Products include Istio Istio.
How do I fix CVE-2021-31921?
Upgrade to a fixed version.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2021-31921 being exploited?
There is no known exploitation of CVE-2021-31921 in the wild and no public exploit code.
Other vulnerabilities in n/a
- CVE-2021-34824 Information disclosure in n/a
- CVE-2026-31837 Istio JWKS resolver to prevent private key material from being exposed when JWKS fetch fails.
- CVE-2021-39155 Authorization Policy Bypass Due to Case Insensitive Host Comparison
- CVE-2021-39156 Fragments in Path May Lead to Authorization Policy Bypass
- CVE-2022-39388 Istio may allow identity impersonation if user has localhost access
Sources
Also known as GHSA-3j84-jghj-gqwg, RHSA-2021:2061, RHSA-2021:2085.