Vulnerability in Microsoft Windows 10

CVE-2018-5174

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.018 (78.2th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 78th percentile — 78.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2018-5174: held from 0.018 to 0.018.

EPSS over last 30 days · oldest: 0.018 · newest: 0.018 · change: 0.000

Affected products

References

Frequently asked questions

What is CVE-2018-5174?
CVE-2018-5174 is a high-severity vulnerability in Microsoft Windows 10. CVSS score: 7.5/10. Published 2018-06-11.
How severe is CVE-2018-5174?
High severity. CVSS v3 base score is 7.5 out of 10.