A security issue has been found in Firefox before 83.0 where, when DNS over HTTPS is in use, it intentionally filters RFC1918 and related IP ranges from the responses as these do not make sense coming from a DoH resolver. However when an IPv4 address was mapped through IPv6, these addresses were erroneously let through, leading to a potential DNS Rebinding attack.
A security issue has been found in Firefox before 83.0 where, when DNS over HTTPS is in use, it intentionally filters RFC1918 and related IP ranges from the responses as these do not make sense coming from a DoH resolver. However when an IPv4 address was mapped through IPv6, these addresses were erroneously let through, leading to a potential DNS Rebinding attack.
https://www.mozilla.org/en-US/security/advisories/mfsa2020-50/#CVE-2020-26961 https://bugzilla.mozilla.org/show_bug.cgi?id=1672528
Vulmon