CVE-2019-9813

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2022-05-24. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Weaponized
8.8EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • Public exploit code is available (Exploit-DB (verified), public exploit)
CISA-KEV: Not listedEPSS PROB: 7%CVSS: 8.8Exploit: Exploit-DB (verified) · public exploitExposed: 0

A fix is available — apply it.

Incorrect handling of __proto__ mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write. This vulnerability affects Firefox < 66.0.1, Firefox ESR < 60.6.1, and Thunderbird < 60.6.1.

CVSS v3
8.8
EG Score
8.8(medium)
EG Risk
70(Track)
EG Risk 70/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity88% × 45%
Exploitation65% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
7%
EPSS %ILE
94%
KEV
Not listed

Published

April 26, 2019

Last Modified

November 25, 2025

Advisory Details (6)

Auto-updated Aug 10, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: redhat.
generic

Security vulnerabilities fixed in Firefox 66.0.1 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2019-09/
generic🔴 Active Exploitation

1538006 - (CVE-2019-9813) ZDI-CAN-8373: Initial code execution: Type confusion in IonMonkey optimizer

https://bugzilla.mozilla.org/show_bug.cgi?id=1538006
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2019:1144
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2019:0966
generic

Security vulnerabilities fixed in Thunderbird 60.6.1 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2019-12/
generic

Security vulnerabilities fixed in Firefox 60.6.1 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2019-10/

Vendor Advisories for CVE-2019-9813(4)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(8)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntufirefox-testsuite (66.0.1+build1-0ubuntu0.16.04.1) @ xenial2026-05-27ubuntu
ubuntuxul-ext-lightning (1:60.6.1+build2-0ubuntu0.16.04.1) @ xenial2026-05-27ubuntu
redhatthunderbird-0:60.6.1-1.el82019-05-13redhat
redhatfirefox-0:60.6.1-1.el82019-05-07redhat
redhatthunderbird-0:60.6.1-1.el7_62019-03-28redhat
redhatthunderbird-0:60.6.1-1.el6_102019-03-28redhat
redhatfirefox-0:60.6.1-1.el7_62019-03-27redhat
redhatfirefox-0:60.6.1-1.el6_102019-03-27redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(6 across 6 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
firefox-esr—60.6.1esr-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
firefox-esr—60.6.1esr-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
firefox-esr—60.6.1esr-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
firefox-esr—60.6.1esr-1—
Debian:8(1)
PackageVulnerable rangeFixed inDependents
firefox-esr45.0.1esr-1 ... 60.6.0esr-1~deb9u1 (131 versions)60.6.1esr-1~deb8u1—
Debian:9(1)
PackageVulnerable rangeFixed inDependents
firefox-esr45.9.0esr-1 ... 60.6.1esr-1~deb8u1 (94 versions)60.6.1esr-1~deb9u1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(4)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 7× in last 7d / 26× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 141 total refreshes for this CVE.

  1. 2026-09-19 15:37 UTCEPSS rescore
  2. 2026-09-18 19:23 UTCEPSS rescore
  3. 2026-09-17 19:22 UTCEPSS rescore
  4. 2026-09-16 14:04 UTCEPSS rescore
  5. 2026-09-16 14:04 UTCEPSS rescore
  6. 2026-09-15 03:06 UTCEPSS rescore
  7. 2026-09-13 16:42 UTCEPSS rescore
  8. 2026-09-12 14:56 UTCEPSS rescore
  9. 2026-09-11 14:48 UTCEPSS rescore
  10. 2026-09-11 09:32 UTCEPSS rescore
  11. 2026-09-08 12:34 UTCOSV refresh
  12. 2026-09-07 15:57 UTCEPSS rescore
  13. 2026-09-06 13:44 UTCEPSS rescore
  14. 2026-09-05 15:24 UTCEPSS rescore
  15. 2026-09-04 13:56 UTCEPSS rescore
  16. 2026-09-04 05:03 UTCEPSS rescore
  17. 2026-09-02 14:08 UTCEPSS rescore
  18. 2026-09-01 03:32 UTCEPSS rescore
  19. 2026-08-30 19:14 UTCEPSS rescore
  20. 2026-08-30 01:18 UTCEPSS rescore
  21. 2026-08-28 21:37 UTCEPSS rescore
  22. 2026-08-27 14:21 UTCEPSS rescore
  23. 2026-08-26 14:42 UTCEPSS rescore
  24. 2026-08-25 13:45 UTCEPSS rescore
  25. 2026-08-21 23:14 UTCOSV refresh
Show 75 more
  1. 2026-08-20 22:51 UTCEPSS rescore
  2. 2026-08-19 17:00 UTCEPSS rescore
  3. 2026-08-18 13:44 UTCEPSS rescore
  4. 2026-08-17 13:43 UTCEPSS rescore
  5. 2026-08-16 14:52 UTCEPSS rescore
  6. 2026-08-16 02:11 UTCEPSS rescore
  7. 2026-08-15 01:26 UTCEPSS rescore
  8. 2026-08-13 21:57 UTCEPSS rescore
  9. 2026-08-12 13:47 UTCEPSS rescore
  10. 2026-08-08 16:33 UTCEPSS rescore
  11. 2026-08-07 16:23 UTCEPSS rescore
  12. 2026-08-06 13:43 UTCEPSS rescore
  13. 2026-08-06 04:54 UTCOSV refresh
  14. 2026-08-05 19:14 UTCEPSS rescore
  15. 2026-08-04 15:06 UTCEPSS rescore
  16. 2026-08-04 10:34 UTCEPSS rescore
  17. 2026-08-03 10:32 UTCEPSS rescore
  18. 2026-08-02 02:23 UTCEPSS rescore
  19. 2026-08-01 04:12 UTCEPSS rescore
  20. 2026-07-30 16:24 UTCEPSS rescore
  21. 2026-07-30 01:27 UTCEPSS rescore
  22. 2026-07-28 15:32 UTCEPSS rescore
  23. 2026-07-26 14:51 UTCEPSS rescore
  24. 2026-07-25 14:14 UTCEPSS rescore
  25. 2026-07-24 14:14 UTCEPSS rescore
  26. 2026-07-23 14:15 UTCEPSS rescore
  27. 2026-07-23 14:15 UTCEPSS rescore
  28. 2026-07-23 01:47 UTCEG score recompute
  29. 2026-07-22 22:30 UTCEG score recompute
  30. 2026-07-22 14:05 UTCEPSS rescore
  31. 2026-07-21 15:22 UTCEPSS rescore
  32. 2026-07-21 15:22 UTCEPSS rescore
  33. 2026-07-20 17:04 UTCEPSS rescore
  34. 2026-07-20 17:04 UTCOSV refresh
  35. 2026-07-19 14:28 UTCEPSS rescore
  36. 2026-07-19 14:28 UTCEPSS rescore
  37. 2026-07-19 02:26 UTCEPSS rescore
  38. 2026-07-19 02:26 UTCEPSS rescore
  39. 2026-07-18 10:02 UTCEPSS rescore
  40. 2026-07-16 16:59 UTCEPSS rescore
  41. 2026-07-16 16:59 UTCEPSS rescore
  42. 2026-07-15 16:55 UTCEPSS rescore
  43. 2026-07-13 22:27 UTCEPSS rescore
  44. 2026-07-12 05:44 UTCEPSS rescore
  45. 2026-07-11 08:24 UTCEPSS rescore
  46. 2026-07-09 19:06 UTCEPSS rescore
  47. 2026-07-08 15:11 UTCEPSS rescore
  48. 2026-07-07 13:43 UTCEPSS rescore
  49. 2026-07-06 16:25 UTCEPSS rescore
  50. 2026-07-06 16:25 UTCEPSS rescore
  51. 2026-07-06 02:20 UTCEPSS rescore
  52. 2026-07-05 02:27 UTCEPSS rescore
  53. 2026-07-04 06:28 UTCEPSS rescore
  54. 2026-07-03 12:26 UTCOSV refresh
  55. 2026-07-01 15:03 UTCEPSS rescore
  56. 2026-07-01 15:03 UTCEPSS rescore
  57. 2026-06-30 23:20 UTCEPSS rescore
  58. 2026-06-30 23:20 UTCEPSS rescore
  59. 2026-06-29 14:04 UTCEPSS rescore
  60. 2026-06-29 14:04 UTCEPSS rescore
  61. 2026-06-28 14:05 UTCEPSS rescore
  62. 2026-06-28 04:54 UTCEPSS rescore
  63. 2026-06-28 04:54 UTCEPSS rescore
  64. 2026-06-27 03:06 UTCEPSS rescore
  65. 2026-06-25 13:47 UTCEPSS rescore
  66. 2026-06-25 13:47 UTCEPSS rescore
  67. 2026-06-24 14:03 UTCEPSS rescore
  68. 2026-06-24 14:03 UTCEPSS rescore
  69. 2026-06-23 21:31 UTCEPSS rescore
  70. 2026-06-23 21:31 UTCEPSS rescore
  71. 2026-06-22 14:23 UTCEPSS rescore
  72. 2026-06-22 14:23 UTCEPSS rescore
  73. 2026-06-21 01:57 UTCEPSS rescore
  74. 2026-06-21 01:57 UTCEPSS rescore
  75. 2026-06-19 19:23 UTCEPSS rescore

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Exploit-DBEDB-46646✓ verified
    First seen Apr 3, 2019

    SpiderMonkey - IonMonkey Compiled Code Fails to Update Inferred Property Types (Type Confusion)

    Open source ↗

Frequently asked(5)

What is CVE-2019-9813?
CVE-2019-9813 is a high vulnerability published on April 26, 2019. Incorrect handling of proto mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write. This vulnerability affects Firefox < 66.0.1, Firefox ESR < 60.6.1, and Thunderbird < 60.6.1.
When was CVE-2019-9813 disclosed?
CVE-2019-9813 was first published in the National Vulnerability Database on April 26, 2019, with the most recent update on November 25, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2019-9813 actively exploited?
CVE-2019-9813 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 7% probability of exploitation in the next 30 days, which ranks it in the top 5.9% of all scored CVEs.
What is the CVSS score of CVE-2019-9813?
CVE-2019-9813 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2019-9813?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-9813, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2019-9813

Explore →

Is Your Infrastructure Affected by CVE-2019-9813?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs