Answer in brief
CVE-2026-53718 records a Medium severity (CVSS 6.4) vulnerability in Envoy Gateway custom backendRef cross-namespace ReferenceGrant bypass. The current sources do not mark it as known exploited. The current feed maps envoyproxy/gateway (generic), github.com/envoyproxy/gateway (go), github.com/envoyproxy/gateway (go), github.com/envoyproxy/gateway (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.4. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps envoyproxy/gateway (generic), github.com/envoyproxy/gateway (go), github.com/envoyproxy/gateway (go), github.com/envoyproxy/gateway (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| envoyproxy/gatewaygeneric | <1.7.4 || >=1.8.0-rc.0 <1.8.1 | 1.7.4, 1.8.1 |
| github.com/envoyproxy/gatewaygo | >=1.8.0-rc.0,<1.8.1 | 1.8.1 |
| github.com/envoyproxy/gatewaygo | <1.7.4 | 1.7.4 |
| github.com/envoyproxy/gatewaygo | >=1.8.0-rc.0 <1.8.1 | 1.8.1 |
| github.com/envoyproxy/gatewaygo | >=0 <1.7.4 | 1.7.4 |
| github.com/envoyproxy/gatewaygo | >=0 <1.7.4 >=1.8.0-rc.0 <1.8.1 | 1.7.4, 1.8.1 |
Published upstream
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 16, 2026
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.
Quoted source text, attributed separately from HOL analysis.