CVSS 3.1
9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVE-2019-9792
The IonMonkey just-in-time (JIT) compiler can leak an internal JS_OPTIMIZED_OUT magic value to the running script during a bailout. This magic value can then be used by JavaScript to achieve memory corruption, which results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.
Severity
- EPSS
- 13% chance of exploitation in the next 30 days; higher than 96% of CVEs (scores of 2026-10-31)
- CWE
- CWE-787
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mozilla:firefox
- mozilla:thunderbird
- redhat:enterprise_linux
- redhat:enterprise_linux_eus
- redhat:enterprise_linux_server_aus
- redhat:enterprise_linux_server_tus
References
- http://packetstormsecurity.com/files/153106/Spidermonkey-IonMonkey-JS_OPTIMIZED_OUT-Value-Leak.html
- https://access.redhat.com/errata/RHSA-2019:0966
- https://access.redhat.com/errata/RHSA-2019:1144
- https://bugzilla.mozilla.org/show_bug.cgi?id=1532599
- https://www.mozilla.org/security/advisories/mfsa2019-07/