CVE-2026-47692

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

MEDIUM

4.3

CVSS Score

Published: June 26, 2026 at 05:59 PM UTC

Updated: October 25, 2026 at 05:10 PM UTC

1 product affected across 1 vendorEnvoy

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Severity

MEDIUM4.3

Exploit prediction

EPSS 0.2%

SSVC

No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Envoy · Envoyproxy

95%

1.34.0 ≤ v < 1.35.131.36.0 ≤ v < 1.36.91.37.0 ≤ v < 1.37.51.38.0 ≤ v < 1.38.3

Affected range stops below 1.35.13, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.36.9, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.37.5, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.38.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://github.com/envoyproxy/envoy/security/advisories/GHSA-wh36-hm39-mm3r

References (1)

x_refsource_CONFIRMVendor Advisory

Source: cverecord

https://github.com/envoyproxy/envoy/security/advisories/GHSA-wh36-hm39-mm3r

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.3MEDIUM[email protected]

Attack Vector: ADJACENT_NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: LOW
Availability: NONE

Vector?

Quick Info

StatusANALYZED

CWE

CWE-130

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