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3.7 Low

CVE-2025-64763 Envoy is a high-performance edge/middle/service proxy

Description

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.

Affected products and versions

Product Affected versions Fixed in
envoy 1.36 1.36.0 → 1.36.2 No fix stated
envoy 1.35 1.35.0 → 1.35.6 No fix stated
envoy 1.34 1.34.0 → 1.34.10 No fix stated
envoy 1.33 earliest → 1.33.12 No fix stated

References

Timeline

  1. Published
  2. Last modified

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