The nsCSPContext::SendReports function in dom/security/nsCSPContext.cpp in Mozilla Firefox before 45.0 and Firefox ESR 38.x before 38.7 does not prevent use of a non-HTTP report-uri for a Content Security Policy (CSP) violation report, which allows remote attackers to cause a denial of service (data overwrite) or possibly gain privileges by specifying a URL of a local file.
Exploitability
AV:NAC:LPR:NUI:RScope
S:UImpact
C:HI:HA:H8.8/CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H