CVSS 3.0
8.8 highCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HCVE-2019-9813
Incorrect handling of __proto__ mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write. This vulnerability affects Firefox < 66.0.1, Firefox ESR < 60.6.1, and Thunderbird < 60.6.1.
Severity
- EPSS
- 6.7% chance of exploitation in the next 30 days; higher than 93% of CVEs (scores of 2026-10-31)
- CWE
- CWE-843
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mozilla:firefox
- mozilla:thunderbird