{"cve":"CVE-2019-9792","nvd":{"published":"2019-04-26T17:29:01.697","modified":"2026-06-17T02:44:21.143","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-787"],"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/"],"products":["mozilla:firefox","mozilla:thunderbird","redhat:enterprise_linux","redhat:enterprise_linux_eus","redhat:enterprise_linux_server_aus","redhat:enterprise_linux_server_tus"],"source":"nvd","synced_at":"2026-10-19T20:56:19.218283075+00:00"},"epss":{"cve":"CVE-2019-9792","score":0.13303,"percentile":0.96393,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}