CVE-2026-73549

medium

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's Utility::copyInternetAddressAndPort and QUIC client-address paths reconstruct scoped IPv6 addresses through addressAsString and Ipv6Instance. The string includes a percent scope identifier that inet_pton cannot parse, causing an exception or abort. Kernel-provided scoped IPv6 destinations in ORIGINAL_DST transparent-proxy deployments, and affected QUIC connection paths, can therefore terminate the process. The relevant scope boundary is that the HTTP use_http_header override rejects scoped addresses earlier; the advisory's crash path requires a kernel-provided original destination or the affected QUIC path. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

References

https://docs.cloud.google.com/support/bulletins/index#gcp-2026-057

https://github.com/envoyproxy/envoy/security/advisories/GHSA-jp5f-qr64-c9vw

https://github.com/envoyproxy/envoy/releases/tag/v1.39.1

https://github.com/envoyproxy/envoy/releases/tag/v1.38.4

https://github.com/envoyproxy/envoy/releases/tag/v1.37.6

https://github.com/envoyproxy/envoy/releases/tag/v1.36.10

https://github.com/envoyproxy/envoy/commit/ab2dca2d65b079768230a7c3d825afeefa330215

https://github.com/envoyproxy/envoy/commit/6e39f4c94deff7a60d382c2d95883e0ea49ff691

https://github.com/envoyproxy/envoy/commit/59b1744a6cb62746db418ac06fc5e359fd25fdb7

https://github.com/envoyproxy/envoy/commit/109e5a5b08ad10d99074cefd55a747a16ee64da7

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-84108

Details

Source: Mitre, NVD

Published: 2026-09-21

Updated: 2026-10-05

Risk Information

CVSS v2

Base Score: 4.9

Vector: CVSS2#AV:N/AC:H/Au:S/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 5.3

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

EPSS

EPSS: 0.00618