CVE-2026-50572: Envoyproxy Envoy

Medium severity, CVSS 5.9. EPSS: 0.7% chance of exploitation in the next 30 days.

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.

Affected products

• Envoyproxy Envoy: before 1.36.10 (fixed in 1.36.10); from 1.37.0, before 1.37.6 (fixed in 1.37.6); from 1.38.0, before 1.38.4 (fixed in 1.38.4); from 1.39.0, before 1.39.1 (fixed in 1.39.1)

Published 2026-09-21. Last modified 2026-10-05.