Medium severity · published Jun 26, 2026
CVE-2026-47692
Envoy: PROXY Protocol v2 header generator emits "skipped" TLVs, causing 65 KB attacker-controlled spillover into the upstream application stream
4.3
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
envoy · envoyproxy
>= 1.38.0, < 1.38.3; >= 1.37.0, < 1.37.5; >= 1.36.0, < 1.36.9; >= 1.34.0, < 1.35.13 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-47692
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-47692
Vendor Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-wh36-hm39-mm3r
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