CVE-2022-21656 (GCVE-0-2022-21656)
Vulnerability from cvelistv5 – Published: 2022-02-22 22:25 – Updated: 2025-04-23 19:01
VLAI
EPSS
VEX
Title
X.509 subjectAltName matching bypass in Envoy
Summary
Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a "type confusion" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted.
Severity
7.4 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-04-23 15:55 UTC
CWE
- CWE-295 - Improper Certificate Validation
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/envoyproxy/envoy/security/advi… | x_refsource_CONFIRM |
| https://github.com/envoyproxy/envoy/commit/bb95af… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| envoyproxy | envoy |
Affected:
< 1.20.2
|
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