The Host Authorization middleware in Action Pack before 220.127.116.11, 18.104.22.168 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.
Created rubygem-actionpack tracking bugs for this issue:
Affects: fedora-all [bug 1930212]
Red Hat Satellite does not make use of the config.hosts setting and is not affected by this CVE.
Hackerone's report: https://hackerone.com/reports/1047447
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):