CVE-2026-47692: Envoy: PROXY Protocol v2 header generator emits "skipped" TLVs, causing 65 KB attacker-controlled spillover into the upstream application stream
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 Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
envoyto a version that resolves this vulnerability.Fixed in 1.35.13 - Upgrade
Upgrade
envoyto a version that resolves this vulnerability.Fixed in 1.36.9 - Upgrade
Upgrade
envoyto a version that resolves this vulnerability.Fixed in 1.37.5 - Upgrade
Upgrade
envoyto a version that resolves this vulnerability.Fixed in 1.38.3
Event History
Frequently Asked Questions
What is the severity of CVE-2026-47692?
The severity of CVE-2026-47692 is medium with a score of 4.8.
How do I fix CVE-2026-47692?
To fix CVE-2026-47692, upgrade Envoy to version 1.35.14 or later, or to one of the recommended patched versions 1.36.10, 1.37.6, or 1.38.4.
What impact does CVE-2026-47692 have on the application?
CVE-2026-47692 allows for 65 KB of attacker-controlled data to spill over into the upstream application stream, potentially leading to data corruption.
Which versions of Envoy are affected by CVE-2026-47692?
CVE-2026-47692 affects Envoy versions from 1.34.0 up to 1.35.13, as well as 1.36.9, 1.37.5, and 1.38.3.
What is the initial report date of CVE-2026-47692?
CVE-2026-47692 was published on June 26, 2026.