Envoy Gateway: Wasm HTTP fetch decompresses gzip without output-size limit
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-789.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| envoyproxy | gateway | before 1.7.4; 1.8.0-rc.0 to before 1.8.1 | 1.7.4, 1.8.1 | Patch available | CNA |
| — | github.com/envoyproxy/gateway (Go) | 1.8.0-rc.0 to before 1.8.1 | 1.8.1 | Patch available | GHSA-cxpq-8v7q-cg56 |
| — | github.com/envoyproxy/gateway (Go) | before 1.7.4 | 1.7.4 | Patch available | GHSA-cxpq-8v7q-cg56 |
- gateway Vendorenvoyproxy Affected before 1.7.4; 1.8.0-rc.0 to before 1.8.1 Fixed in 1.7.4, 1.8.1 Patch available CNA
- github.com/envoyproxy/gateway (Go) Vendor— Affected 1.8.0-rc.0 to before 1.8.1 Fixed in 1.8.1 Patch available GHSA-cxpq-8v7q-cg56
- github.com/envoyproxy/gateway (Go) Vendor— Affected before 1.7.4 Fixed in 1.7.4 Patch available GHSA-cxpq-8v7q-cg56
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:envoyproxy:gateway:*:*:*:*:*:*:*:* | — | — | envoyproxy |
- cpe:2.3:a:envoyproxy:gateway:*:*:*:*:*:*:*:* Versions — — ·envoyproxy
Remediation
- Fix · CNA gateway (envoyproxy) Fixed in 1.7.4, 1.8.1
- Fix · GHSA-cxpq-8v7q-cg56 github.com/envoyproxy/gateway (Go) Fixed in 1.8.1 Advisory →
- Fix · GHSA-cxpq-8v7q-cg56 github.com/envoyproxy/gateway (Go) Fixed in 1.7.4 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Connectivity Link 1 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-53716
- 2026-10-03 Alias added: GHSA-cxpq-8v7q-cg56
References
Other 10
- https://github.com/envoyproxy/gateway/security/advisories/GHSA-cxpq-8v7q-cg56
- https://github.com/envoyproxy/gateway/pull/9171
- https://github.com/envoyproxy/gateway/pull/9172
- https://github.com/envoyproxy/gateway/pull/9173
- https://github.com/envoyproxy/gateway/commit/5a78db82b7cf4fc5bebbeda2c50952892038a464
- https://github.com/envoyproxy/gateway/commit/96e2b750868a459ace4b8b68e6a6e4fb0152b9b7
- https://github.com/envoyproxy/gateway/commit/b4737180c7e597490c6363075c565fa8cf24eead
- https://github.com/envoyproxy/gateway/releases/tag/v1.7.4
- https://github.com/envoyproxy/gateway/releases/tag/v1.8.1
- https://github.com/envoyproxy/gateway
More envoyproxy vulnerabilities
- TI-2026-79288 Out-of-bounds write in Google Brotli decoder KEVCVSS 4.0CRITICAL 9.2
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2024-20001 HTTP/2: CPU exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
- TI-2024-18524 HTTP/2: memory exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
- TI-2023-12215 Envoy client may fake the header `x-envoy-original-path` CVSS 3.1CRITICAL 9.1
- TI-2023-18002 Envoy vulnerable to OAuth2 credentials exploit with permanent validity CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-53716 · CVE Program
- CVE-2026-53716 · NVD
- FIRST EPSS
- GHSA-cxpq-8v7q-cg56 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-53716 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences