Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. Prior to 1.7.4 and 1.8.1, an HTTPRoute can use an extension-managed custom backendRef to reference a backend resource in another namespace without a matching Gateway API ReferenceGrant in the target namespace. The custom-backend branch in internal/gatewayapi/route.go omits validateBackendNamespace, allowing the route-owning namespace to bind to and use the resource without the backend namespace owner's consent and violating the Gateway API cross-namespace authorization model.
This issue is fixed in versions 1.7.4 and 1.8.1.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
High
Difficult to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
Low
Partial data modification
Availability
Low
Partial disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 9
https://github.com/envoyproxy/gateway/commit/5a78db82b7cf4fc5bebbeda2c509528920…
security-advisories@github.com
https://github.com/envoyproxy/gateway/commit/96e2b750868a459ace4b8b68e6a6e4fb01…
security-advisories@github.com
https://github.com/envoyproxy/gateway/commit/b4737180c7e597490c6363075c565fa8cf…
security-advisories@github.com
https://github.com/envoyproxy/gateway/pull/9171
security-advisories@github.com
https://github.com/envoyproxy/gateway/pull/9172
security-advisories@github.com
https://github.com/envoyproxy/gateway/pull/9173
security-advisories@github.com
https://github.com/envoyproxy/gateway/releases/tag/v1.7.4
security-advisories@github.com
https://github.com/envoyproxy/gateway/releases/tag/v1.8.1
security-advisories@github.com
https://github.com/envoyproxy/gateway/security/advisories/GHSA-fcrp-7gc2-93g7
security-advisories@github.com