CVE-2021-43824

HighCVSS 7.5/10Last modified Jun 17, 2026

Description

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.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-476

Affected software

Vendor	Product	Versions
envoyproxy	envoy	>= 1.20.0, < 1.20.2; >= 1.19.0, < 1.19.3; < 1.18.6; >= 1.21.0, < 1.21.1

References

https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253aPatch, Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2pIssue Tracking, Third Party Advisory
https://github.com/envoyproxy/envoy/commit/9371333230b1a6e1be2eccf4868771e11af6253aPatch, Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-vj5m-rch8-5r2pIssue Tracking, Third Party Advisory

Timeline

Published: Feb 22, 2022
Last modified: Jun 17, 2026
NVD status: Modified

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