CVE-2021-43826

mediumpriority · track · 30EPSS 0.011 · 64 %ileDEEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.06% (64th) EPSS
CVSS 4.3 · medium
Is it mine?
53 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-22

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedservicemesh-proxy-0:2.1.2-4.el8.ppc64le as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-0:2.1.2-4.el8.s390x as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-0:2.1.2-4.el8.src as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-0:2.1.2-4.el8.x86_64 as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-debuginfo-0:2.1.2-4.el8.ppc64le as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-debuginfo-0:2.1.2-4.el8.s390x as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-debuginfo-0:2.1.2-4.el8.x86_64 as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-debugsource-0:2.1.2-4.el8.ppc64le as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-debugsource-0:2.1.2-4.el8.s390x as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-debugsource-0:2.1.2-4.el8.x86_64 as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
  • Fixedservicemesh-proxy-wasm-0:2.1.2-4.el8.noarch as a component of OpenShift Service Mesh 2.1redhat_csaf

    The OpenShift Service Mesh Release Notes provide information on the features and known issues: https://docs.openshift.com/container-platform/latest/service_mesh/v2x/servicemesh-release-notes.html

    https://access.redhat.com/errata/RHSA-2022:1275
02

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–7.5

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 2.9
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comexploitability 3.9 · impact 3.6
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Red Hat Product Security US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USCWE-416US
05

affected products (53)

Products and version ranges known to be affected.

showing 20 of 53
06

advisories (3)

Vendor and ecosystem advisories describing this.

  • RHSA-2022:1275Red Hat Security Advisory: Red Hat OpenShift Service Mesh 2.1.2 security update2022-04-07csaf · redhat_csafUS

    Red Hat OpenShift Service Mesh 2.1.2 Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

  • WID-SEC-W-2022-0970Red Hat OpenShift: Mehrere SchwachstellenDeutsch2022-04-07csaf · cert_bundDE

    Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Red Hat OpenShift ausnutzen, um einen Denial-of-Service-Zustand zu verursachen und Sicherheitsmaßnahmen zu umgehen.

  • BIT-envoy-2021-43826Crash when tunneling TCP over HTTP in Envoy2024-03-06vendor · osvUS

    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.

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdosvcert_bundnvdredhat_csafNVDCVE.orgMITRE
published 2022-02-22modified 2026-06-17
09

references (11)

External citations — patches, advisories, analysis.

scry

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