CVE-2022-21657 Information

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. In affected versions Envoy does not restrict the set of certificates it accepts from the peer either as a TLS client or a TLS server to only those certificates that contain the necessary extendedKeyUsage (id-kp-serverAuth and id-kp-clientAuth respectively). This means that a peer may present an e-mail certificate (e.g. id-kp-emailProtection) either as a leaf certificate or as a CA in the chain and it will be accepted for TLS. This is particularly bad when combined with the issue described in pull request 630 in that it allows a Web PKI CA that is intended only for use with S/MIME and thus exempted from audit or supervision to issue TLS certificates that will be accepted by Envoy. As a result Envoy will trust upstream certificates that should not be trusted. There are no known workarounds to this issue. Users are advised to upgrade.

CVSS Vector

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

Reference

https://github.com/envoyproxy/envoy/pull/630 https://github.com/envoyproxy/envoy/security/advisories/GHSA-837m-wjrv-vm5g

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

HIGH

Base Score

NONE

Base Severity

6.5