CVE-2021-43826

Crash when tunneling TCP over HTTP in Envoy

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Link Tags
https://github.com/envoyproxy/envoy/security/advisories/GHSA-cmx3-fvgf-83mf issue tracking third party advisory
https://github.com/envoyproxy/envoy/commit/ce0ae309057a216aba031aff81c445c90c6ef145 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-43826?
CVE-2021-43826 has been scored as a high severity vulnerability.
How to fix CVE-2021-43826?
To fix CVE-2021-43826, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43826 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43826 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43826?
CVE-2021-43826 affects envoyproxy envoy.
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