CVE-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.
Key facts
- CVSS score
- 9.8 (v3.1)
- Severity
- CRITICAL
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness (CWE)
- CWE-787
- EPSS score
- 13.2% (96th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2019-19154)
- Published
- April 26, 2019
- NVD last modified
- June 17, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2019-19154 in the EU Vulnerability Database. Last updated in EUVD on August 4, 2024.
View on the EU Vulnerability DatabaseAffected products
- mozilla / firefox
- mozilla / thunderbird
- redhat / enterprise linux
- redhat / enterprise linux eus
- redhat / enterprise linux eus
- redhat / enterprise linux eus
- redhat / enterprise linux server aus
- redhat / enterprise linux server aus
- redhat / enterprise linux server tus
- redhat / enterprise linux server tus
Certified products that may be affected
25 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.
- Red Hat Enterprise Linux 8 NSS Cryptographic Module - Red Hat, Inc. - FIPS 140 5513 - active
- Red Hat Enterprise Linux 8 Kernel Cryptographic API - Red Hat, LLC - FIPS 140 5461 - active
- Red Hat Enterprise Linux 8 Kernel Cryptographic API - Red Hat, Inc. - FIPS 140 5089 - active
- Red Hat Enterprise Linux 8 OpenSSL Cryptographic Module - Red Hat®, Inc. - FIPS 140 4642 - historical
- Red Hat Enterprise Linux 8 NSS Cryptographic Module - Red Hat®, Inc. - FIPS 140 4458 - historical
See all 25 in the Security Certifications Explorer.
References
- http://packetstormsecurity.com/files/153106/Spidermonkey-IonMonkey-JS_OPTIMIZED_OUT-Value-Leak.html(Exploit, Third Party Advisory, VDB Entry)
- https://access.redhat.com/errata/RHSA-2019:0966(Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2019:1144(Third Party Advisory)
- https://bugzilla.mozilla.org/show_bug.cgi?id=1532599(Exploit, Issue Tracking, Vendor Advisory)
- https://www.mozilla.org/security/advisories/mfsa2019-07/(Vendor Advisory)
- https://www.mozilla.org/security/advisories/mfsa2019-08/(Vendor Advisory)
- https://www.mozilla.org/security/advisories/mfsa2019-11/(Vendor Advisory)
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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