Public bug reported: Ubuntu 18.04.5 LTS apache2 2.4.29-1ubuntu4.14
A IPv4 client accesses an Apache2 server configured with proxypass to a IPv6 capable backend. X-Forwarded-For header with the IPv4 is not passed to the backend. Work around is to force IPv4 with ProxySourceAddress <IPv4-address>. Expected behaviour is that it would pass the client's IPv4 without the work around. Even though the Proxy backend connection is IPv6, this does not mean that the X-Forwarded-For header becomes null. Documentation highlighted statement seems to underline this: "IPv4-over-IPv6 Mapped Addresses As with httpd in general, any IPv4-over-IPv6 mapped addresses are recorded in their IPv4 representation" ** Affects: apache2 (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1895877 Title: proxypass IPv4-over-IPv6 excludes X-Forwarded-For header To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apache2/+bug/1895877/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs