SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-43826

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…

HIGH 7.5EPSS 1.06%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.06%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.06% probability · 63th percentile
CISA KEV
Not listed
Weakness
CWE-416
Affected
envoyproxy/envoy
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.