Buffer Overflow Vulnerability in Envoy Proxy Affects Multiple Versions
CVE-2026-47692

4.8MEDIUM

Key Information:

Vendor

Envoyproxy

Status
Envoy
Vendor
CVE Published:
26 June 2026

What is CVE-2026-47692?

A buffer overflow vulnerability has been identified in Envoy Proxy, an open-source edge and service proxy utilized in cloud-native applications. The flaw exists within the PROXY Protocol v2 header generator, specifically in versions 1.34.0 through 1.38.3, where it emits Type-Length-Value (TLV) fields exceeding the maximum allowable length of 65535 bytes. This discrepancy can lead to a mismatch between the bytes written and the specified length field in the header, potentially allowing malicious users to inject smuggled bytes in upstream requests. Users of the affected versions are encouraged to upgrade to the patched versions to mitigate this risk.

Affected Version(s)

envoy >= 1.38.0, < 1.38.3 < 1.38.0, 1.38.3

envoy >= 1.37.0, < 1.37.5 < 1.37.0, 1.37.5

envoy >= 1.36.0, < 1.36.9 < 1.36.0, 1.36.9

References

https://github.com/envoyproxy/envoy/security/advisories/G...
x_refsource_CONFIRM

CVSS V3.1

Score:
4.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.