Envoy Gateway: Authentication Bypass via Improper Input Validation in EnvoyExtensionPolicy Lua Allows Secret Disclosure

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L

EPSS

• CVE-2026-53713: 0.43% estimated exploitation activity in the next 30 days; percentile 37.62 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact The toabsolutenormalizedpath function (security.lua:28-43) does not collapse redundant path separators (// → /). On Linux, //etc/passwd is equivalent to /etc/passwd (POSIX path semantics), but iscriticalpath fails to match the double-slash variant because //etc/passwd does not start with /etc/. This allows Lua code submitted as an EnvoyExtensionPolicy to read arbitrary files from the gateway controller pod's filesystem during Strict validation (the default), including: /etc/passwd Kubernetes SA tokens via //var/run/secrets/kubernetes.io/serviceaccount/token TLS certificates via //certs/... Process environment via //proc/self/environ These credentials can be used to read sensitive information from the K8s API Server or from the Gateway XDS server. Patches This has been patched in versions = v1.7.4 and v1.8.1 - Collapse redundant path separators (// to /) so double-slash variants like //etc/passwd and //var/run/secrets/... are matched by the critical-path check. - Rewrite the…

Published by the source

16 Jul 2026, 19:23 UTC

Last modified by the source

16 Jul 2026, 19:23 UTC

Source last checked

26 Oct 2026, 15:25 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-wcrf-9vrr-854f

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# Patch Next advisory brief: CVE-2026-53713

Advisory: Envoy Gateway: Authentication Bypass via Improper Input Validation in EnvoyExtensionPolicy Lua Allows Secret Disclosure
IDs: CVE-2026-53713, GHSA-wcrf-9vrr-854f
Record: https://patchnext.com/advisories/cve-2026-53713 (revision 1, source checked 26 Oct 2026, 15:25 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/envoyproxy/gateway 1.8.1, 1.7.4. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/envoyproxy/gateway: affected >= 1.8.0-rc.0, < 1.8.1; < 1.7.4; fixed in 1.8.1, 1.7.4

## Suggested inspection (read-only)
- Go github.com/envoyproxy/gateway: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/envoyproxy/gateway.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-wcrf-9vrr-854f (GitHub-reviewed advisory GHSA-wcrf-9vrr-854f lists affected ranges: Go github.com/envoyproxy/gateway >=1.8.0-rc.0 =0 <1.7.4)

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