CVE-2021-39191

Published: 3 September 2021

mod_auth_openidc is an authentication/authorization module for the Apache 2.x HTTP server that functions as an OpenID Connect Relying Party, authenticating users against an OpenID Connect Provider. In versions prior to 2.4.9.4, the 3rd-party init SSO functionality of mod_auth_openidc was reported to be vulnerable to an open redirect attack by supplying a crafted URL in the `target_link_uri` parameter. A patch in version 2.4.9.4 made it so that the `OIDCRedirectURLsAllowed` setting must be applied to the `target_link_uri` parameter. There are no known workarounds aside from upgrading to a patched version.

Priority

Cvss 3 Severity Score

6.1

Score breakdown

Status

Package	Release	Status
libapache2-mod-auth-openidc Launchpad, Ubuntu, Debian	bionic	Needed
	focal	Needed
	hirsute	Ignored (end of life)
	impish	Ignored (end of life)
	jammy	Needs triage
	kinetic	Ignored (end of life, was needs-triage)
	lunar	Ignored (end of life, was needs-triage)
	mantic	Needs triage
	noble	Needs triage
	trusty	Does not exist
	upstream	Needs triage
	xenial	Needs triage

Severity score breakdown

Parameter	Value
Base score	6.1
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Changed
Confidentiality	Low
Integrity impact	Low
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

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