Envoy: ext_authz - RawHttpClientImpl onSuccess 0x0 segfault
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's HTTP external-authorization client can retain a stale request callback after a request is rejected. When RawHttpClientImpl::onSuccess later processes the authorization response, it can invoke callbacks_ after the callback owner has been destroyed, causing a use-after-free and process crash under production traffic. The relevant scope boundary is that the vulnerable path uses the HTTP ext_authz client; the advisory does not establish the same trigger for unrelated filters. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| envoyproxy | envoy | before 1.36.10; 1.37.0 to before 1.37.6; 1.38.0 to before 1.38.4; 1.39.0 to before 1.39.1 | 1.36.10, 1.37.6, 1.38.4, 1.39.1 | Patch available | CNA |
- envoy Vendorenvoyproxy Affected before 1.36.10; 1.37.0 to before 1.37.6; 1.38.0 to before 1.38.4; 1.39.0 to before 1.39.1 Fixed in 1.36.10, 1.37.6, 1.38.4, 1.39.1 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* | before 1.36.10; 1.37.0 to before 1.37.6; 1.38.0 to before 1.38.4; 1.39.0 to before 1.39.1 | Vulnerable | envoyproxy |
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* Versions before 1.36.10; 1.37.0 to before 1.37.6; 1.38.0 to before 1.38.4; 1.39.0 to before 1.39.1 Vulnerable ·envoyproxy
Remediation
- Fix · CNA envoy (envoyproxy) Fixed in 1.36.10, 1.37.6, 1.38.4, 1.39.1
Red Hat 5 advisories
- RHSA-2026:65121 Released 2026-09-08 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.4.2
- Red Hat OpenShift Service Mesh 3.4 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
- RHSA-2026:65115 Released 2026-09-08 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.3.7
- Red Hat OpenShift Service Mesh 3.3 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
- RHSA-2026:65113 Released 2026-09-08 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.2.9
- Red Hat OpenShift Service Mesh 3.2 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
Show 2 more Red Hat advisories
- RHSA-2026:65112 Released 2026-09-08 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.1.12
- Red Hat OpenShift Service Mesh 3.1 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
- RHSA-2026:65106 Released 2026-09-08 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.0.15
- Red Hat OpenShift Service Mesh 3.0 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat OpenShift Service Mesh 3.0 | Fixed | RHSA-2026:65106 |
| Red Hat OpenShift Service Mesh 3.1 | Fixed | RHSA-2026:65112 |
| Red Hat OpenShift Service Mesh 3.2 | Fixed | RHSA-2026:65113 |
| Red Hat OpenShift Service Mesh 3.3 | Fixed | RHSA-2026:65115 |
| Red Hat OpenShift Service Mesh 3.4 | Fixed | RHSA-2026:65121 |
Not affected: 5 products
- Red Hat OpenShift Service Mesh 3.0
- Red Hat OpenShift Service Mesh 3.1
- Red Hat OpenShift Service Mesh 3.2
- Red Hat OpenShift Service Mesh 3.3
- Red Hat OpenShift Service Mesh 3.4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-50572
References
Patch 4
- https://github.com/envoyproxy/envoy/commit/8dacef38337aeffd62866b5c5910104b63b33db8
- https://github.com/envoyproxy/envoy/commit/a49085623654e27e9ad6298928557644b849d7ce
- https://github.com/envoyproxy/envoy/commit/c1b29534a294cb0999e99e1fe0de000310165f03
- https://github.com/envoyproxy/envoy/commit/c524571ffad517ba650d9563f85afa89194e2cfb
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- TI-2023-12215 Envoy client may fake the header `x-envoy-original-path` CVSS 3.1CRITICAL 9.1
- TI-2023-18002 Envoy vulnerable to OAuth2 credentials exploit with permanent validity CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-50572 · CVE Program
- CVE-2026-50572 · NVD
- FIRST EPSS
- CVE-2026-50572 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences