CVE-2019-9814: Critical severity Mozilla Firefox vulnerability
Last updated 25 August 2025
Other sources
Mozilla developers and community members Christian Holler, Andrei Ciure, Julien Cristau, Jan de Mooij, Jan Varga, Marcia Knous, André Bargull, and Philipp reported memory safety bugs present in Firefox 66. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code.
Mozilla developers and community members reported memory safety bugs present in Firefox 66. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 67.
— Launchpad
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Firefoxto a version that resolves this vulnerability.Fixed in 67 - Upgrade
Upgrade
debian/firefoxto a version that resolves this vulnerability.Fixed in 152.0-1
Event History
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
What is CVE-2019-9814?
CVE-2019-9814 is a memory safety vulnerability present in Firefox 66 that can lead to memory corruption with enough effort.
How severe is CVE-2019-9814?
CVE-2019-9814 has a severity rating of critical with a CVSS score of 9.0.
Which software versions are affected by CVE-2019-9814?
Firefox versions up to and excluding 67.0 are affected by CVE-2019-9814.
How can I fix CVE-2019-9814?
To fix CVE-2019-9814, upgrade your Firefox browser to version 67.0 or higher.
Where can I find more information about CVE-2019-9814?
More information about CVE-2019-9814 can be found at the following references: [Bugzilla](https://bugzilla.mozilla.org/buglist.cgi?bug_id=1527592%2C1534536%2C1520132%2C1543159%2C1539393%2C1459932%2C1459182%2C1516425), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2019-13/)