CVE-2026-47207 Envoy crashes if multiple unexpected ext_proc responses are packed into one gRPC message
A malicious ext_proc server can crash Envoy by sending crafted gRPC messages, causing a use-after-free error.
- 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-2026-47207?
CVE-2026-47207 is a medium-severity use after free 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 1.34.0 until 1.35.13, 1.36.9, 1.37.5, and 1.38.3, Envoy crashes if an ext_proc server sends a single gRPC message containing multiple, specially crafted ProcessingResponse messages. This can occur when the first response in the batch causes the gRPC stream object to be destroyed, leading to a use-after-free error when Envoy attempts to process subsequent responses in the same gRPC message. This vulnerability is fixed in 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
Weakness: CWE-416
Which versions are affected by CVE-2026-47207?
1 open source package ship an affected version, including envoy. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
envoy Bitnami | From 1.34.0 | 1.35.13, 1.36.9, 1.37.5, 1.38.3 |
Products include Envoyproxy Envoy.
How do I fix CVE-2026-47207?
Upgrade envoy to a fixed version for your release line: 1.35.13, 1.36.9, 1.37.5 or 1.38.3.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-47207 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47207 exists.
Other vulnerabilities in Envoyproxy Envoy
Sources
Also known as BIT-envoy-2026-47207, GHSA-68cv-hq5f-g6xv.