CVE-2026-47204 Envoy: grpc_stats filter segfault on Connect protocol requests to direct_response routes
An unauthenticated attacker can crash the Envoy proxy process by sending a specific Connect protocol request to a direct_response route, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-47204?
CVE-2026-47204 is a medium-severity vulnerability in Envoyproxy Envoy, published on 26 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.26.0 until 1.35.13, 1.36.9, 1.37.5, and 1.38.3, the envoy.filters.http.grpc_stats filter crashes (null pointer dereference / segfault) when a Connect protocol request (Content-Type: application/connect+proto or application/connect+json) hits a direct_response route. A single unauthenticated HTTP request crashes the Envoy process. This vulnerability is fixed in 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
Weakness: CWE-476
Which versions are affected by CVE-2026-47204?
1 open source package ship an affected version, including envoy. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
envoy Bitnami | From 1.26.0 | 1.35.13, 1.36.9, 1.37.5, 1.38.3 |
Products include Envoyproxy Envoy.
How do I fix CVE-2026-47204?
Upgrade envoy to a fixed version for your release line: 1.35.13, 1.36.9, 1.37.5 or 1.38.3.
Is CVE-2026-47204 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47204 exists.
Other vulnerabilities in Envoyproxy Envoy
Sources
Also known as BIT-envoy-2026-47204, GHSA-3jxh-8p6x-7pf6.