{"api_version":"1","generated_at":"2026-04-22T23:31:20+00:00","cve":"CVE-2021-39191","urls":{"html":"https://cve.report/CVE-2021-39191","api":"https://cve.report/api/cve/CVE-2021-39191.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-39191","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-39191"},"summary":{"title":"CVE-2021-39191","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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