Bug 2057271 (CVE-2022-21656)

Summary:	CVE-2022-21656 envoy: X.509 subjectAltName matching (and nameConstraints) bypass
Product:	[Other] Security Response	Reporter:	Avinash Hanwate <ahanwate>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	jwendell, ovanders, rcernich
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	envoy 1.20.2	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in envoy. The default_validator.cc implementation used to implement the default certificate validation routines has a "type confusion" bug when processing subjectAltNames.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2050760

Description Avinash Hanwate 2022-02-23 06:25:19 UTC

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.

https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e
https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2