Buffer overflow in Mozilla Firefox

CVE-2019-9800

Mozilla developers and community members reported memory safety bugs present in Firefox 66, Firefox ESR 60.6, and Thunderbird 60.6. 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 Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Vulnerability class: Buffer Overflow

EPSS: 0.018 (75.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-9800?
CVE-2019-9800 is a critical-severity vulnerability in Mozilla Firefox, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2019-07-23.
How severe is CVE-2019-9800?
Critical severity. CVSS v3 base score is 9.8 out of 10.