What is the CVSS score of CVE-2026-47204?

CVE-2026-47204 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.4%.

Is there a patch available for CVE-2026-47204?

Yes, a patch is available for CVE-2026-47204. Update the affected software to the latest version immediately.

Envoy Proxy CVE-2026-47204

EUVD-2026-39824 HIGH

NULL Pointer Dereference (CWE-476)

2026-06-26 GitHub_M

Denial Of Service Null Pointer Dereference Red Hat Envoy Suse Envoyproxy

7.5

CVSS 3.1 · NVD

Severity by source

Vendor (GitHub_M) PRIMARY

MEDIUM

qualitative

NVD

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

vuln.today AI

7.5 HIGH

Vendor description states unauthenticated exploitation, overriding official PR:L; pure availability crash, no confidentiality or integrity impact.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H

SUSE

HIGH

qualitative

Red Hat

6.5 MEDIUM

qualitative

Primary rating from Vendor (GitHub_M).

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Severity Changed

Jun 27, 2026 - 20:37 NVD

MEDIUM HIGH

CVSS changed

Jun 27, 2026 - 20:37 NVD

6.5 (MEDIUM) 7.5 (HIGH)

Patch available

Jun 26, 2026 - 19:02 EUVD

Analysis Generated

Jun 26, 2026 - 18:36 vuln.today

DescriptionNVD

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.

AnalysisAI

The envoy.filters.http.grpc_stats HTTP filter in Envoy versions 1.26.0 through the pre-fix releases crashes with a null pointer dereference when a Connect protocol request (Content-Type: application/connect+proto or application/connect+json) is routed to a direct_response route, terminating the Envoy process entirely. The vendor description states a single unauthenticated HTTP request is sufficient to trigger the crash, giving any network-reachable attacker a trivial one-packet denial of service against affected deployments. No confirmed active exploitation (absent from CISA KEV) and no public exploit code has been identified at time of analysis, but the trivial trigger condition makes this high practical risk for any deployment with both preconditions present.

Technical ContextAI

Envoy (cpe:2.3:a:envoyproxy:envoy) is a high-performance C++ Layer 7 proxy and service mesh data plane widely deployed in Kubernetes environments via Istio and comparable projects. The envoy.filters.http.grpc_stats filter is an HTTP filter plugin that collects telemetry for gRPC and Connect protocol traffic. The root cause is CWE-476 (Null Pointer Dereference): when the filter processes a Connect protocol request - identified by Content-Type: application/connect+proto or application/connect+json - against a route configured with a direct_response action, the filter dereferences a null pointer, likely because it assumes upstream cluster context (e.g., a cluster object for stats labeling) that does not exist on a direct_response route. The resulting SIGSEGV crashes the entire Envoy worker process. The Connect protocol is a modern HTTP-based RPC protocol; direct_response routes return a static response without upstream forwarding. The combination of these two features exposes a code path that does not safely handle the absence of upstream state, a regression introduced in version 1.26.0.

RemediationAI

Upgrade Envoy to one of the vendor-confirmed patched releases: 1.35.13, 1.36.9, 1.37.5, or 1.38.3, as documented in GitHub Security Advisory GHSA-3jxh-8p6x-7pf6 at https://github.com/envoyproxy/envoy/security/advisories/GHSA-3jxh-8p6x-7pf6. If an immediate upgrade is not feasible, two targeted workarounds exist: first, remove or disable the envoy.filters.http.grpc_stats HTTP filter from any filter chains that contain direct_response routes - this eliminates the vulnerable code path entirely, with the trade-off of losing Connect and gRPC statistics for those routes; second, remove or convert direct_response routes in filter chains where the grpc_stats filter is active, replacing them with upstream cluster routes, which carries operational complexity but preserves statistics collection. Organizations consuming Envoy through a distribution such as Istio or AWS App Mesh should track patched distribution releases that incorporate the above Envoy fix versions rather than patching Envoy independently.