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CVE-2022-21656

HIGH severity · CVSS 7.4 · CWE-295
7.4CVSS HIGH

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.

Impact & exploitability

Attack vectorNetwork
Attack complexityHigh
Privileges requiredNone
User interactionNone
Confidentiality impactHigh
Integrity impactHigh
Availability impactNone
Exploit probability (EPSS)1%

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

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e ↗