{"schemaVersion":3,"id":"CVE-2021-39191","aliases":["UBUNTU-CVE-2021-39191","DEBIAN-CVE-2021-39191"],"status":"published","duplicateOf":null,"title":null,"description":"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. 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