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 a
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.
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Thunderbird | unspecified |
| Mozilla | Firefox ESR | unspecified |
| Mozilla | Firefox | unspecified |
Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.
For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.
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No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.