CVE-2019-9814

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-07-23 · updated 2026-06-17
Weakness: CWE-787

Description

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.

Affected products

Mozilla Firefox: before 67.0 — fixed in 67.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 67.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/buglist.cgi?bug_id=1527592%2C1534536%2C1520132%2C1543159%2C1539393%2C1459932%2C1459182%2C1516425
https://www.mozilla.org/security/advisories/mfsa2019-13/
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1527592%2C1534536%2C1520132%2C1543159%2C1539393%2C1459932%2C1459182%2C1516425
https://www.mozilla.org/security/advisories/mfsa2019-13/

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