cvedb.io
CVE-2026-48743
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2026-06-26T18:17:00.173 · Last modified 2026-06-29T18:27:36.190

Summary

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, Envoy can translate a downstream HTTP/3 request that is complete at the transport layer (HEADERS with FIN / headers-only close) but still carries a nonzero Content-Length into a complete upstream HTTP/1 request with unresolved body debt. In an HTTP/1 upstream deployment where the origin replies before reading the declared body and keeps the connection reusable, the beginning of the next Envoy-generated upstream request can be consumed as the first request's body. The remaining bytes are then parsed by the origin as a new HTTP/1 request. This was reproduced as a route-bypass/desync: direct /pwn was denied by Envoy, but the second downstream H3 stream received

Affected products

envoyproxy — envoy

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.