{"schemaVersion":3,"id":"CVE-2021-22903","aliases":["UBUNTU-CVE-2021-22903","GHSA-5hq2-xf89-9jxq"],"status":"published","duplicateOf":null,"title":null,"description":"The actionpack ruby gem before 6.1.3.2 suffers from a possible open redirect vulnerability. Specially crafted Host headers in combination with certain \"allowed host\" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website. This is similar to CVE-2021-22881. Strings in config.hosts that do not have a leading dot are converted to regular expressions without proper escaping. 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