CVE-2026-53716: Envoyproxy Gateway

Medium severity, CVSS 6.5. EPSS: 0.7% chance of exploitation in the next 30 days.

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, getFileFromGZ in internal/wasm/httpfetcher.go calls io.ReadAll on a gzip.Reader without limiting decompressed output when a tenant-controlled EnvoyExtensionPolicy.spec.wasm[].code.http.url points to a reachable compressed Wasm payload. The 256 MiB compressed-input cap does not constrain the expanded size, no operator Wasm URL allowlist exists, and the optional sha256 check occurs only after decompression, so a comparatively small gzip stream can force a multi-gigabyte allocation in the shared controller. The resulting out-of-memory termination restarts the controller, re-reconciles the persistent custom resource, and can create a persistent cross-tenant control-plane outage. This issue is fixed in versions 1.7.4 and 1.8.1.

Affected products

• Envoyproxy Gateway: before 1.7.4 (fixed in 1.7.4); from 1.8.0-rc.0, before 1.8.1 (fixed in 1.8.1)

Published 2026-09-14. Last modified 2026-09-30.