CVE-2019-11747
This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.
Does this matter?
Lower severity and a low EPSS score (1.19%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- EPSS
- 1.19% probability · 68th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-665
- Affected
- mozilla/firefox · mozilla/firefox esr
- Source
- security@mozilla.org
EPSS 1.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00011.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00017.html
- https://bugzilla.mozilla.org/show_bug.cgi?id=1564481Issue Tracking, Permissions Required, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2019-25/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2019-26/Vendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00011.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00017.html
- https://bugzilla.mozilla.org/show_bug.cgi?id=1564481Issue Tracking, Permissions Required, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2019-25/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2019-26/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.