The mozilla::net::IsValidReferrerPolicy function in Mozilla Firefox before 49.0 allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a Content Security Policy (CSP) referrer directive with zero values.
https://www.mozilla.org/security/advisories/mfsa2016-85/
https://security.gentoo.org/glsa/201701-15
https://bugzilla.mozilla.org/show_bug.cgi?id=1289085