CVE-2022-21656

X.509 subjectAltName matching bypass in Envoy

Description

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.

Categories

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.02%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2022-21656?
CVE-2022-21656 has been scored as a high severity vulnerability.
How to fix CVE-2022-21656?
To fix CVE-2022-21656, 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-2022-21656 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-21656 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-2022-21656?
CVE-2022-21656 affects envoyproxy envoy.
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