CVE-2017-7821

Publication date 2 October 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

A vulnerability where WebExtensions can download and attempt to open a file of some non-executable file types. This can be triggered without specific user interaction for the file download and open actions. This could be used to trigger known vulnerabilities in the programs that handle those document types. This vulnerability affects Firefox < 56.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
firefox	18.04 LTS bionic	Fixed 56.0+build6-0ubuntu1
	17.10 artful	Fixed 56.0+build6-0ubuntu1
	17.04 zesty	Fixed 56.0+build6-0ubuntu0.17.04.1
	16.04 LTS xenial	Fixed 56.0+build6-0ubuntu0.16.04.1
	14.04 LTS trusty	Fixed 56.0+build6-0ubuntu0.14.04.1

Severity score breakdown

Parameter	Value
Base score	9.8 · Critical
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

USN-3435-1
Firefox vulnerabilities
2 October 2017