The Mozilla Maintenance Service "helper.exe" application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 52.2 and Firefox < 54.
http://www.securityfocus.com/bid/99057
http://www.securitytracker.com/id/1038689
https://bugzilla.mozilla.org/show_bug.cgi?id=1215648
https://sourceforge.net/p/nsis/bugs/1125/
Source: MITRE
Published: 2018-06-11
Updated: 2019-10-03
Type: CWE-276
Base Score: 3.6
Vector: AV:L/AC:L/Au:N/C:N/I:P/A:P
Impact Score: 4.9
Exploitability Score: 3.9
Severity: LOW
Base Score: 5.5
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Impact Score: 3.6
Exploitability Score: 1.8
Severity: MEDIUM