CVE-2021-22881

The Host Authorization middleware in Action Pack before 6.1.2.1, 6.0.3.5 suffers from an 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. Impacted applications will have allowed hosts with a leading dot. When an allowed host contains a leading dot, a specially crafted `Host` header can be used to redirect to a malicious website.

• CWE-601
• CWE-601

• http://www.openwall.com/lists/oss-security/2021/05/05/2Mailing List, Mitigation, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/08/20/1Mailing List, Mitigation, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/12/14/5Exploit, Mailing List, Patch
• https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization/Patch, Third Party Advisory
• https://discuss.rubyonrails.org/t/cve-2021-22881-possible-open-redirect-in-host-authorization-middleware/77130Mitigation, Patch, Vendor Advisory
• https://hackerone.com/reports/1047447Exploit, Patch, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3/
• http://www.openwall.com/lists/oss-security/2021/05/05/2Mailing List, Mitigation, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/08/20/1Mailing List, Mitigation, Third Party Advisory
• http://www.openwall.com/lists/oss-security/2021/12/14/5Exploit, Mailing List, Patch
• https://benjamin-bouchet.com/cve-2021-22881-faille-de-securite-dans-le-middleware-hostauthorization/Patch, Third Party Advisory
• https://discuss.rubyonrails.org/t/cve-2021-22881-possible-open-redirect-in-host-authorization-middleware/77130Mitigation, Patch, Vendor Advisory
• https://hackerone.com/reports/1047447Exploit, Patch, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XQ3NS4IBYE2I3MVMGAHFZBZBIZGHXHT3/

Published

Feb 11, 2021

Last Modified

Jun 17, 2026

Status

Modified

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