CVE-2019-11747

MEDIUM

Mozilla Firefox < 69 and Firefox ESR < 68.1 - HSTS Setting Removal

Title source: llm
STIX 2.1

Description

The "Forget about this site" feature in the History pane is intended to remove all saved user data that indicates a user has visited a site. This includes removing any HTTP Strict Transport Security (HSTS) settings received from sites that use it. Due to a bug, sites on the pre-load list also have their HSTS setting removed. On the next visit to that site if the user specifies an http: URL rather than secure https: they will not be protected by the pre-loaded HSTS setting. After that visit the site's HSTS setting will be restored. This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.

References (5)

Core 5
Core References
Issue Tracking, Permissions Required, Vendor Advisory x_refsource_misc
https://bugzilla.mozilla.org/show_bug.cgi?id=1564481
Vendor Advisory x_refsource_confirm
https://www.mozilla.org/security/advisories/mfsa2019-25/
Vendor Advisory x_refsource_confirm
https://www.mozilla.org/security/advisories/mfsa2019-26/

Scores

CVSS v3 6.5
EPSS 0.0120
EPSS Percentile 63.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Details

CWE
CWE-665
Status published
Products (2)
mozilla/firefox < 69.0
mozilla/firefox_esr < 68.1.0
Published Sep 27, 2019
Tracked Since Feb 18, 2026