The maintenance service in Mozilla Firefox before 47.0 and Firefox ESR 45.x before 45.2 on Windows does not prevent MAR extracted-file modification during updater execution, which might allow local users to gain privileges via a Trojan horse file.
Severity
CVSS 3.0
7.8 high
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.3% chance of exploitation in the next 30 days; higher than 27% of CVEs (scores of 2026-10-31)