CVE-2021-43824

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 2026-10-27

Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions a crafted request crashes Envoy when a CONNECT request is sent to JWT filter configured with regex match. This provides a denial of service attack vector. The only workaround is to not use regex in the JWT filter. Users are advised to upgrade.

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

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

ssvc

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

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

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-476USCWE-476US

affected products (53)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat OpenShift Container Platform 4all versionscert_bundDEcpe:/a:redhat:openshift:container_platform_4
envoyproxy envoy≤ < 1.18.6enisa_euvdEU
envoyproxy envoy1.19.0, → 1.19.3enisa_euvdEU
envoyproxy envoy1.20.0, → 1.20.2enisa_euvdEU
envoyproxy envoy1.21.0, → 1.21.1enisa_euvdEU
envoyproxy envoy< 1.18.6nvdUScpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
envoyproxy envoy1.19.0 → 1.19.3nvdUScpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
envoyproxy envoy1.20.0 → 1.20.2nvdUScpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
envoyproxy envoy1.21.0 → 1.21.1nvdUScpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
Bitnami envoy< 1.18.6osvUSpkg:bitnami/envoy
Bitnami envoy1.19.0 → 1.19.3osvUSpkg:bitnami/envoy
Bitnami envoy1.20.0 → 1.20.2osvUSpkg:bitnami/envoy
Bitnami envoy1.21.0 → 1.21.1osvUSpkg:bitnami/envoy
servicemesh-0:2.1.2-4.el8.ppc64le as a component of OpenShift Service Mesh 2.1all versionsnot affectedredhat_csafUS
servicemesh-0:2.1.2-4.el8.s390x as a component of OpenShift Service Mesh 2.1all versionsnot affectedredhat_csafUS
servicemesh-0:2.1.2-4.el8.src as a component of OpenShift Service Mesh 2.1all versionsnot affectedredhat_csafUS

showing 20 of 53

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-2021-43824Null pointer dereference in envoy2024-03-06vendor · osvUS
Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions a crafted request crashes Envoy when a CONNECT request is sent to JWT filter configured with regex match. This provides a denial of service attack vector. The only workaround is to not use regex in the JWT filter. Users are advised to upgrade.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund nvd redhat_csaf NVD CVE.org MITRE

published 2022-02-22modified 2026-06-17

references (11)

External citations — patches, advisories, analysis.

scry

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