CVE-2018-5174

Publication date 11 June 2018

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

In the Windows 10 April 2018 Update, Windows Defender SmartScreen honors the "SEE_MASK_FLAG_NO_UI" flag associated with downloaded files and will not show any UI. Files that are unknown and potentially dangerous will be allowed to run because SmartScreen will not prompt the user for a decision, and if the user is offline all files will be allowed to be opened because Windows won't prompt the user to ask what to do. Firefox incorrectly sets this flag when downloading files, leading to less secure behavior from SmartScreen. Note: this issue only affects Windows 10 users running the April 2018 update or later. It does not affect other Windows users or other operating systems. This vulnerability affects Thunderbird < 52.8, Thunderbird ESR < 52.8, Firefox < 60, and Firefox ESR < 52.8.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
firefox	18.04 LTS bionic	Not affected
	17.10 artful	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not in release
thunderbird	18.04 LTS bionic	Not affected
	17.10 artful	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	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	High
Availability impact	None
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N