Some special resource URIs will cause a non-exploitable crash if loaded with optional parameters following a '?' in the parsed string. This could lead to denial of service (DOS) attacks. This vulnerability affects Firefox < 63. References: https://bugzilla.mozilla.org/show_bug.cgi?id=1422456 External References: https://www.mozilla.org/en-US/security/advisories/mfsa2018-26/#CVE-2018-12401