CVE-2026-12299

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreHIGH confidence

Score 5.4 from GitHub Security Advisory published 2026-06-16. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 5.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
5.4
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.4Exploit: NoneExposed: 0

A fix is available — apply it.

JIT miscompilation in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

CVSS v3
5.4
EG Score
5.4(high)
EG Risk
—
EPSS
22.8%
KEV
Not listed

Published

June 16, 2026

Last Modified

July 15, 2026

Advisory Details (4)

Auto-updated Jun 16, 2026
No patch confirmed yet.
generic

Security Vulnerabilities fixed in Firefox ESR 115.37 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-59/
generic

Security Vulnerabilities fixed in Firefox ESR 140.12 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-58/
generic

Security Vulnerabilities fixed in Firefox 152 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-57/
generic

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2043139

Vendor Advisories for CVE-2026-12299(20)

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

Patch Availability(21)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatthunderbird-0:140.12.0-1.el9_22026-07-15redhat
redhatthunderbird-0:140.12.0-1.el8_82026-07-14redhat
redhatthunderbird-0:140.12.0-1.el8_62026-07-14redhat
redhatthunderbird-0:140.12.0-1.el8_42026-07-14redhat
redhatfirefox-0:140.12.0-1.el7_92026-07-13redhat
redhatthunderbird-0:140.12.0-1.el10_02026-07-13redhat
redhatfirefox-0:140.12.0-1.el9_42026-07-13redhat
redhatthunderbird-0:140.12.0-1.el9_42026-07-13redhat
redhatthunderbird-0:140.12.0-1.el9_62026-07-13redhat
redhatfirefox-0:140.12.0-1.el9_62026-07-09redhat
redhatfirefox-0:140.12.0-1.el8_62026-07-09redhat
redhatfirefox-0:140.12.0-1.el8_42026-07-07redhat
redhatfirefox-0:140.12.0-1.el10_02026-07-07redhat
redhatfirefox-0:140.12.0-1.el8_82026-07-07redhat
redhatfirefox-0:140.12.0-1.el9_22026-07-07redhat
redhatthunderbird-0:140.12.0-1.el8_102026-06-30redhat
redhatthunderbird-0:140.12.0-1.el10_22026-06-29redhat
redhatthunderbird-0:140.12.0-1.el9_82026-06-25redhat
redhatfirefox-0:140.12.0-1.el10_22026-06-22redhat
redhatfirefox-0:140.12.0-1.el8_102026-06-22redhat
redhatfirefox-0:140.12.0-1.el9_82026-06-22redhat

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.

Weakness Classification(2)

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

Additional Vendor Advisories

(1)

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 9× in last 7d / 79× 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.

  1. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:24 UTCEPSS rescore
  3. 2026-07-20 17:08 UTCEPSS rescore
  4. 2026-07-19 14:30 UTCEPSS rescore
  5. 2026-07-19 02:28 UTCEPSS rescore
  6. 2026-07-18 10:04 UTCEPSS rescore
  7. 2026-07-16 17:02 UTCEPSS rescore
  8. 2026-07-16 08:27 UTCVendor advisory
  9. 2026-07-16 08:27 UTCGHSA enrichment
  10. 2026-07-15 16:57 UTCEPSS rescore
  11. 2026-07-15 07:50 UTCVendor advisory
  12. 2026-07-15 07:50 UTCGHSA enrichment
  13. 2026-07-15 02:00 UTCEPSS rescore
  14. 2026-07-14 07:14 UTCVendor advisory
  15. 2026-07-14 07:14 UTCGHSA enrichment
  16. 2026-07-13 22:30 UTCEPSS rescore
  17. 2026-07-13 06:12 UTCEPSS rescore
  18. 2026-07-13 05:43 UTCVendor advisory
  19. 2026-07-13 05:43 UTCGHSA enrichment
  20. 2026-07-12 05:46 UTCEPSS rescore
  21. 2026-07-12 05:11 UTCVendor advisory
  22. 2026-07-12 05:11 UTCGHSA enrichment
  23. 2026-07-11 08:27 UTCEPSS rescore
  24. 2026-07-11 04:42 UTCVendor advisory
  25. 2026-07-11 04:42 UTCGHSA enrichment
Show 72 more
  1. 2026-07-10 04:16 UTCVendor advisory
  2. 2026-07-10 04:16 UTCGHSA enrichment
  3. 2026-07-09 19:10 UTCEPSS rescore
  4. 2026-07-09 03:43 UTCVendor advisory
  5. 2026-07-09 03:43 UTCGHSA enrichment
  6. 2026-07-08 15:15 UTCEPSS rescore
  7. 2026-07-08 15:15 UTCEPSS rescore
  8. 2026-07-08 03:17 UTCVendor advisory
  9. 2026-07-08 03:16 UTCGHSA enrichment
  10. 2026-07-07 13:46 UTCEPSS rescore
  11. 2026-07-07 02:49 UTCVendor advisory
  12. 2026-07-07 02:49 UTCGHSA enrichment
  13. 2026-07-06 16:27 UTCEPSS rescore
  14. 2026-07-06 02:23 UTCEPSS rescore
  15. 2026-07-06 02:13 UTCVendor advisory
  16. 2026-07-06 02:13 UTCGHSA enrichment
  17. 2026-07-05 02:30 UTCEPSS rescore
  18. 2026-07-05 02:30 UTCEPSS rescore
  19. 2026-07-05 01:45 UTCVendor advisory
  20. 2026-07-05 01:45 UTCGHSA enrichment
  21. 2026-07-04 06:31 UTCEPSS rescore
  22. 2026-07-04 01:19 UTCVendor advisory
  23. 2026-07-04 01:19 UTCGHSA enrichment
  24. 2026-07-03 00:47 UTCVendor advisory
  25. 2026-07-03 00:47 UTCGHSA enrichment
  26. 2026-07-02 00:22 UTCVendor advisory
  27. 2026-07-02 00:22 UTCGHSA enrichment
  28. 2026-07-01 15:06 UTCEPSS rescore
  29. 2026-07-01 15:06 UTCEPSS rescore
  30. 2026-06-30 23:56 UTCVendor advisory
  31. 2026-06-30 23:56 UTCGHSA enrichment
  32. 2026-06-30 23:22 UTCEPSS rescore
  33. 2026-06-29 23:30 UTCVendor advisory
  34. 2026-06-29 23:30 UTCGHSA enrichment
  35. 2026-06-29 14:06 UTCEPSS rescore
  36. 2026-06-28 23:04 UTCVendor advisory
  37. 2026-06-28 23:04 UTCGHSA enrichment
  38. 2026-06-28 14:07 UTCEPSS rescore
  39. 2026-06-28 04:56 UTCEPSS rescore
  40. 2026-06-28 04:56 UTCEPSS rescore
  41. 2026-06-27 22:38 UTCVendor advisory
  42. 2026-06-27 22:38 UTCGHSA enrichment
  43. 2026-06-27 03:08 UTCEPSS rescore
  44. 2026-06-26 22:12 UTCVendor advisory
  45. 2026-06-26 22:12 UTCGHSA enrichment
  46. 2026-06-25 21:45 UTCVendor advisory
  47. 2026-06-25 21:45 UTCGHSA enrichment
  48. 2026-06-25 13:49 UTCEPSS rescore
  49. 2026-06-24 21:19 UTCVendor advisory
  50. 2026-06-24 21:19 UTCGHSA enrichment
  51. 2026-06-24 14:05 UTCEPSS rescore
  52. 2026-06-23 21:32 UTCEPSS rescore
  53. 2026-06-23 20:53 UTCVendor advisory
  54. 2026-06-23 20:53 UTCGHSA enrichment
  55. 2026-06-22 20:23 UTCVendor advisory
  56. 2026-06-22 20:23 UTCGHSA enrichment
  57. 2026-06-22 14:25 UTCEPSS rescore
  58. 2026-06-22 14:25 UTCEPSS rescore
  59. 2026-06-21 19:55 UTCGHSA enrichment
  60. 2026-06-21 14:56 UTCEPSS rescore
  61. 2026-06-21 14:56 UTCEPSS rescore
  62. 2026-06-21 01:59 UTCEPSS rescore
  63. 2026-06-21 01:59 UTCEPSS rescore
  64. 2026-06-20 19:27 UTCGHSA enrichment
  65. 2026-06-19 19:25 UTCEPSS rescore
  66. 2026-06-19 18:34 UTCEG score recompute▲ 5.40
  67. 2026-06-19 18:34 UTCGHSA enrichment
  68. 2026-06-18 17:52 UTCEPSS rescore
  69. 2026-06-17 17:53 UTCEPSS rescore
  70. 2026-06-16 15:47 UTCNVD updateCVSS v3 → 5.4 · severity → MEDIUM
  71. 2026-06-16 13:49 UTCEG score recompute
  72. 2026-06-16 13:46 UTCNVD updatefirst tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-12299?
CVE-2026-12299 is a medium vulnerability published on June 16, 2026. JIT miscompilation in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
When was CVE-2026-12299 disclosed?
CVE-2026-12299 was first published in the National Vulnerability Database on June 16, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12299 actively exploited?
CVE-2026-12299 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 22.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-12299?
CVE-2026-12299 has a CVSS v3.1 base score of 5.4 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-12299?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12299, 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

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