Improper Certificate Validation in envoy - CVE-2022-21656
Published: February 22, 2022 / Updated: August 26, 2026
Vulnerability identifier: #VU145838
CSH Severity: Low
CVSS v4: 2.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2022-21656
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass X.509 subjectAltName matching and nameConstraints checks.
The vulnerability exists due to improper certificate validation in X.509 subjectAltName matching and nameConstraints processing when validating certificates. A remote user can present a specially crafted certificate to bypass X.509 subjectAltName matching and nameConstraints checks.
Affected software
envoy
How to mitigate CVE-2022-21656
Install security update from vendor's website.
envoy - update to 1.20.2