CVE-2019-9811
CVSS v3
8.3
HIGH
EPSS Score
2.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
As part of a winning Pwn2Own entry, a researcher demonstrated a sandbox escape by installing a malicious language pack and then opening a browser feature that used the compromised translation. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.
Technical details
- Published
- 2019-07-23
Frequently asked questions
What is CVE-2019-9811?
As part of a winning Pwn2Own entry, a researcher demonstrated a sandbox escape by installing a malicious language pack and then opening a browser feature that used the compromised translation. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.
Is CVE-2019-9811 actively exploited?
Active exploitation of CVE-2019-9811 has not been confirmed. Its EPSS score was 2.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2019-9811?
CVE-2019-9811 has a CVSS v3 base score of 8.3 (HIGH severity).
Is CVE-2019-9811 affecting your environment?
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