CVE-2017-7761

Publication date 11 June 2018

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
firefox	17.04 zesty	Not affected
	16.10 yakkety	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not in release

Notes

chrisccoulson

Windows only

Severity score breakdown

Parameter	Value
Base score	5.5 · Medium
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	High
Availability impact	None
Vector	CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N