CVE-2019-9820
Mozilla: Use-after-free of ChromeEventHandler by DocShell
Severity
ImportantRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · May 22, 2019
Updated · November 22, 2025
Description
A use-after-free vulnerability can occur in the chrome event handler when it is freed while still in use. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.
Statement
In general, this flaw cannot be exploited through email in Thunderbird because scripting is disabled when reading mail, but it is potentially a risk in browser or browser-like contexts.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.0 · 9.8CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-416 · Use After Free