CVE-2021-43826

Crash when tunneling TCP over HTTP in Envoy

State: Published
Severity: 7.5 High
Published: Feb 22, 2022
Updated: Apr 23, 2025
Reserved: Nov 16, 2021

Description

Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions of Envoy a crash occurs when configured for :ref:`upstream tunneling <envoy_v3_api_field_extensions.filters.network.tcp_proxy.v3.TcpProxy.tunneling_config>` and the downstream connection disconnects while the the upstream connection or http/2 stream is still being established. There are no workarounds for this issue. Users are advised to upgrade.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	GitHub_M

Weaknesses

CWE-416 Use After Free

Affected Products

Product	Versions
envoyenvoyproxy	< 1.18.6Affected >= 1.19.0, < 1.19.3Affected >= 1.20.0, < 1.20.2Affected >= 1.21.0, < 1.21.1Affected

References

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