Mozilla: IonMonkey leaks JS_OPTIMIZED_OUT magic value to script
Published Apr 26, 2019
9.8
CRITICALCVSS 3.1
EPSS 13.20%
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.
Affected products
-
- Version unspecifiedStatusaffectedConstraints<66
- Version
-
- Version unspecifiedStatusaffectedConstraints<60.6
- Version
-
- Version unspecifiedStatusaffectedConstraints<60.6
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mozilla | Firefox | n/a |
| ||||||
| Mozilla | Firefox ESR | n/a |
| ||||||
| Mozilla | Thunderbird | n/a |
|
Configuration 1
Configuration 2
- 8.0
- 8.1
- 8.2
- 8.4
- 8.2
- 8.4
- 8.2
- 8.4
No data.
Red Hat Enterprise Linux 6
firefox-0:60.6.0-3.el6_10
Fixed · RHSA-2019:0623
Red Hat Enterprise Linux 6
thunderbird-0:60.6.1-1.el6_10
Fixed · RHSA-2019:0680
Red Hat Enterprise Linux 7
firefox-0:60.6.0-3.el7_6
Fixed · RHSA-2019:0622
Red Hat Enterprise Linux 7
thunderbird-0:60.6.1-1.el7_6
Fixed · RHSA-2019:0681
Red Hat Enterprise Linux 8
firefox-0:60.6.1-1.el8
Fixed · RHSA-2019:0966
Red Hat Enterprise Linux 8
thunderbird-0:60.6.1-1.el8
Fixed · RHSA-2019:1144
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | firefox-0:60.6.0-3.el6_10 | Fixed | RHSA-2019:0623 |
| Red Hat Enterprise Linux 6 | thunderbird-0:60.6.1-1.el6_10 | Fixed | RHSA-2019:0680 |
| Red Hat Enterprise Linux 7 | firefox-0:60.6.0-3.el7_6 | Fixed | RHSA-2019:0622 |
| Red Hat Enterprise Linux 7 | thunderbird-0:60.6.1-1.el7_6 | Fixed | RHSA-2019:0681 |
| Red Hat Enterprise Linux 8 | firefox-0:60.6.1-1.el8 | Fixed | RHSA-2019:0966 |
| Red Hat Enterprise Linux 8 | thunderbird-0:60.6.1-1.el8 | Fixed | RHSA-2019:1144 |
No package ranges for this CVE.
Remediation
Red Hat statement
In general, this flaw be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but are potentially risks in browser or browser-like contexts.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:L/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 2, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (32 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 13.20% (0.13197) | 96.26th | v5 (v2026.06.15) |
| Jun 15, 2026 | 13.20% (0.13197) | 95.86th | v5 (v2026.06.15) |
| Nov 21, 2025 | 19.72% (0.19723) | 95.20th | v4 (v2025.03.14) |
| Nov 18, 2025 | 27.76% (0.27762) | 96.16th | v4 (v2025.03.14) |
| Mar 30, 2025 | 19.81% (0.19813) | 94.97th | v4 (v2025.03.14) |
| Mar 29, 2025 | 43.69% (0.43691) | 96.32th | v4 (v2025.03.14) |
| Mar 17, 2025 | 19.81% (0.19813) | 94.98th | v4 (v2025.03.14) |
| Mar 5, 2025 | 28.94% (0.28938) | 96.97th | v3 (v2023.03.01) |
| Dec 17, 2024 | 26.47% (0.26466) | 96.75th | v3 (v2023.03.01) |
| Dec 12, 2024 | 17.25% (0.17248) | 96.29th | v3 (v2023.03.01) |
| Aug 4, 2024 | 18.09% (0.18093) | 96.20th | v3 (v2023.03.01) |
| Jun 12, 2024 | 13.89% (0.13886) | 95.68th | v3 (v2023.03.01) |
| May 24, 2024 | 10.39% (0.10391) | 94.97th | v3 (v2023.03.01) |
| May 7, 2024 | 10.58% (0.10582) | 95.00th | v3 (v2023.03.01) |
| Apr 19, 2024 | 9.10% (0.09096) | 94.53th | v3 (v2023.03.01) |
| Apr 4, 2024 | 9.06% (0.09065) | 94.51th | v3 (v2023.03.01) |
| Mar 17, 2024 | 12.29% (0.12285) | 95.25th | v3 (v2023.03.01) |
| Feb 14, 2024 | 21.57% (0.21566) | 96.28th | v3 (v2023.03.01) |
| Dec 22, 2023 | 19.25% (0.19247) | 95.81th | v3 (v2023.03.01) |
| Dec 10, 2023 | 14.56% (0.14562) | 95.21th | v3 (v2023.03.01) |
| Oct 23, 2023 | 14.90% (0.14897) | 95.17th | v3 (v2023.03.01) |
| Aug 20, 2023 | 13.41% (0.13410) | 94.87th | v3 (v2023.03.01) |
| Jul 22, 2023 | 15.60% (0.15601) | 95.18th | v3 (v2023.03.01) |
| Apr 2, 2023 | 13.63% (0.13633) | 94.70th | v3 (v2023.03.01) |
| Mar 7, 2023 | 13.23% (0.13230) | 94.61th | v3 (v2023.03.01) |
| Mar 6, 2023 | 10.21% (0.10212) | 94.60th | v2 (v2022.01.01) |
| Apr 1, 2022 | 10.21% (0.10212) | 94.14th | v2 (v2022.01.01) |
| Feb 4, 2022 | 36.61% (0.36610) | 97.00th | v2 (v2022.01.01) |
| Feb 3, 2022 | 5.82% (0.05819) | 80.57th | v1 |
| Jan 6, 2022 | 5.82% (0.05819) | 80.37th | v1 |
| Sep 1, 2021 | 5.82% (0.05819) | 89.04th | v1 |
| Apr 14, 2021 | 5.82% (0.05819) | 0.00th | v1 |
References (12)
- http://packetstormsecurity.com/files/153106/Spidermonkey-IonMonkey-JS_OPTIMIZED_OUT-Value-Leak.html x_refsource_MISCExploitThird Party AdvisoryVDB Entry
- https://access.redhat.com/errata/RHSA-2019:0966 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2019:1144 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2019-9792 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1532599 x_refsource_MISCExploitIssue TrackingVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1690677 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2019-9792
- https://www.cve.org/CVERecord?id=CVE-2019-9792
- https://www.mozilla.org/en-US/security/advisories/mfsa2019-08/#CVE-2019-9792
- https://www.mozilla.org/security/advisories/mfsa2019-07/ x_refsource_MISCVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2019-08/ x_refsource_MISCVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2019-11/ x_refsource_MISCVendor Advisory
Change history (0)
No recorded changes yet.