CVE-2025-64763
Fixed upstream EPSS <1%CVSS 3.7
Envoy is a high-performance edge/middle/service proxy. In 1.33.12, 1.34.10, 1.35.6, 1.36.2, and earlier, when Envoy is configured in TCP proxy mode to handle CONNECT requests, it accepts client data before issuing a 2xx response and forwards that data to the upstream TCP connection. If a forwarding proxy upstream from Envoy then responds with a non-2xx status, this can cause a de-synchronized CONNECT tunnel state. By default Envoy continues to allow early CONNECT data to avoid disrupting existing deployments. The envoy.reloadable_features.reject_early_connect_data runtime flag can be set to reject CONNECT requests that send data before a 2xx response when intermediaries upstream from Envoy may reject establishment of a CONNECT tunnel.
Products: envoyproxy envoy
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Go | github.com/envoyproxy/envoy | 1.36.3 |
| Go | github.com/envoyproxy/envoy | 1.35.7 |
| Go | github.com/envoyproxy/envoy | 1.34.11 |
| Go | github.com/envoyproxy/envoy | 1.33.13 |