CVE-2026-47692

MEDIUM

Envoy: PROXY Protocol v2 header generator emits "skipped" TLVs, causing 65 KB attacker-controlled spillover into the upstream application stream

Title source: cna
STIX 2.1

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.34.0 until 1.35.13, 1.36.9, 1.37.5, and 1.38.3, PROXY Protocol v2 header generator emits TLVs beyond the maximum length of 65535 bytes, causing a mismatch between bytes written and the length field in the header. This can result in smuggled bytes on the upstream request. This vulnerability is fixed in 1.35.13, 1.36.9, 1.37.5, and 1.38.3.

References (1)

Core 1
Core References

Scores

CVSS v3 4.8
EPSS 0.0014
EPSS Percentile 3.7%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-130
Status published
Products (5)
envoyproxy/envoy 1.34.0 - 1.35.13
envoyproxy/envoy >= 1.34.0, < 1.35.13
envoyproxy/envoy >= 1.36.0, < 1.36.9
envoyproxy/envoy >= 1.37.0, < 1.37.5
envoyproxy/envoy >= 1.38.0, < 1.38.3
Published Jun 26, 2026
Tracked Since Jun 26, 2026