Envoy: PROXY Protocol v2 header generator emits "skipped" TLVs, causing 65 KB attacker-controlled spillover into the upstream application stream
Summary
| CVE | CVE-2026-47692 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-26 18:16:59 UTC |
| Updated | 2026-06-27 20:09:48 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 4.3 MEDIUM from [email protected]
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS: 0.002180000 probability, percentile 0.121590000 (date 2026-06-29)
Problem Types: CWE-130 | CWE-130 CWE-130: Improper Handling of Length Parameter Inconsistency
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 4.3 | MEDIUM | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| 3.1 | [email protected] | Secondary | 4.8 | MEDIUM | CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:L |
| 3.1 | CNA | DECLARED | 4.8 | MEDIUM | CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:L |
CVSS v3.1 Breakdown
Attack Vector
AdjacentAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
LowAvailability
NoneCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Envoyproxy | Envoy | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Envoyproxy | Envoy | affected >= 1.38.0, < 1.38.3 | Not specified |
| CNA | Envoyproxy | Envoy | affected >= 1.37.0, < 1.37.5 | Not specified |
| CNA | Envoyproxy | Envoy | affected >= 1.36.0, < 1.36.9 | Not specified |
| CNA | Envoyproxy | Envoy | affected >= 1.34.0, < 1.35.13 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/envoyproxy/envoy/security/advisories/GHSA-wh36-hm39-mm3r | [email protected] | github.com | Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.