CVE-2018-5174 Information

Description

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.

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Reference

http://www.securityfocus.com/bid/104136 http://www.securitytracker.com/id/1040896 https://bugzilla.mozilla.org/show_bug.cgi?id=1447080 https://www.mozilla.org/security/advisories/mfsa2018-11/ https://www.mozilla.org/security/advisories/mfsa2018-12/ https://www.mozilla.org/security/advisories/mfsa2018-13/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

HIGH

Base Score

NONE

Base Severity

7.5