CVE-2026-53717 is a medium-severity (CVSS 6.5) CWE-789 vulnerability in github.com/envoyproxy/gateway. A fix is available for github.com/envoyproxy/gateway — see the affected versions and patch details below.
Envoy Gateway: OCI layer extraction allocates make([]byte, h.Size) from untrusted tar header
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-53717.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-53717 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
github.com/envoyproxy/gateway🐹github.com/envoyproxy/gatewayReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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, internal/wasm/imagefetcher.go follows tenant-controlled EnvoyExtensionPolicy spec.wasm[].code.image.url values to Docker or OCI Wasm layers, and extractWasmPluginBinary uses the untrusted tar-header h.Size value to allocate memory before validating the entry name or declared size. A small PAX or GNU tar header can therefore claim a multi-terabyte entry even though the surrounding LimitReader restricts only the bytes read from the stream, and no registry allowlist prevents a permitted tenant from selecting an attacker-controlled registry that the controller can reach. The allocation is attempted for every tar entry and can cause an unrecoverable Go runtime out-of-memory failure; because the custom resource persists, reconciliation repeatedly crash-loops the shared controller and causes a single-request, non-volumetric, cluster-wide control-plane denial of service. This issue is fixed in versions 1.7.4 and 1.8.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/envoyproxy/gateway | ≥ 1.8.0-rc.0&&< 1.8.1 | 1.8.1go get github.com/envoyproxy/gateway@v1.8.1 |
| 🐹Go | github.com/envoyproxy/gateway | all versions | 1.7.4go get github.com/envoyproxy/gateway@v1.7.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/envoyproxy/gateway, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/envoyproxy/gateway to 1.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-53717 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is CVE-2026-53717 in your dependencies?
Find it across Go, including transitive dependencies.