Vulnerability in Mozilla Firefox

CVE-2019-11747

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.

Vulnerability class: Dirty Pipe (CVE-2022-0847)

EPSS: 0.012 (64.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-11747?
CVE-2019-11747 is a medium-severity vulnerability in Mozilla Firefox, classified under Improper Initialization. CVSS score: 6.5/10. Published 2019-09-27.
How severe is CVE-2019-11747?
Medium severity. CVSS v3 base score is 6.5 out of 10.