The type inference system allows the compilation of functions that can cause type confusions between arbitrary objects when compiled through the IonMonkey just-in-time (JIT) compiler and when the constructor function is entered through on-stack replacement (OSR). This allows for possible arbitrary reading and writing of objects during an exploitable crash. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-1722-1 firefox-esr security update
Debian DLA Debian DLA DLA-1743-1 thunderbird security update
Debian DSA Debian DSA DSA-4411-1 firefox-esr security update
Debian DSA Debian DSA DSA-4420-1 thunderbird security update
Ubuntu USN Ubuntu USN USN-3918-1 Firefox vulnerabilities
Ubuntu USN Ubuntu USN USN-3918-2 Firefox vulnerabilities
Ubuntu USN Ubuntu USN USN-3927-1 Thunderbird vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 25 Nov 2025 18:00:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
Vendors & Products Mozilla firefox Esr

cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2024-08-04T22:01:54.733Z

Reserved: 2019-03-14T00:00:00

Link: CVE-2019-9791

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2019-04-26T17:29:01.523

Modified: 2025-11-25T17:50:16.803

Link: CVE-2019-9791

cve-icon Redhat

Severity : Critical

Publid Date: 2019-03-20T00:00:00Z

Links: CVE-2019-9791 - Bugzilla

cve-icon OpenCVE Enrichment

No data.