CVE-2022-21657

X.509 Extended Key Usage and Trust Purposes bypass in Envoy

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.

Category

6.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Link Tags
https://github.com/envoyproxy/envoy/security/advisories/GHSA-837m-wjrv-vm5g issue tracking third party advisory
https://github.com/envoyproxy/envoy/pull/630 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2022-21657?
CVE-2022-21657 has been scored as a medium severity vulnerability.
How to fix CVE-2022-21657?
To fix CVE-2022-21657, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-21657 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-21657 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-21657?
CVE-2022-21657 affects envoyproxy envoy.
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