CVE-2026-12296

CRITICALPre-NVD 9.69.6—
EchelonGraph scoreMEDIUM confidence

Score 9.6 from GitHub Security Advisory (severity: CRITICAL) published 2026-06-16. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.6; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
9.6
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 9.6Exploit: NoneExposed: 0

A fix is available — apply it.

Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

CVSS v3
9.6
EG Score
9.6(medium)
EPSS
31.8%
KEV
Not listed

Published

June 16, 2026

Last Modified

July 15, 2026

Advisory Details (5)

Auto-updated Jun 18, 2026
No patch confirmed yet.
generic

Security Vulnerabilities fixed in Thunderbird 140.12 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-61/
generic

Security Vulnerabilities fixed in Thunderbird 152 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-60/
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=2040515

Vendor Advisories for CVE-2026-12296(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
redhatthunderbird-0:140.12.0-1.el9_62026-07-13redhat
redhatfirefox-0:140.12.0-1.el7_92026-07-13redhat
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.el10_02026-07-13redhat
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.el9_22026-07-07redhat
redhatfirefox-0:140.12.0-1.el8_82026-07-07redhat
redhatfirefox-0:140.12.0-1.el8_42026-07-07redhat
redhatfirefox-0:140.12.0-1.el10_02026-07-07redhat
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.el8_102026-06-22redhat
redhatfirefox-0:140.12.0-1.el9_82026-06-22redhat
redhatfirefox-0:140.12.0-1.el10_22026-06-22redhat

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 21× in last 7d / 273× 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 307 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-12296?
CVE-2026-12296 is a critical vulnerability published on June 16, 2026. Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
When was CVE-2026-12296 disclosed?
CVE-2026-12296 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-2026-12296 actively exploited?
CVE-2026-12296 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 31.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-12296?
CVE-2026-12296 has a CVSS v3.1 base score of 9.6 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-12296?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12296, 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

Explore the affected products and dependency analysis for CVE-2026-12296

Explore →

Is Your Infrastructure Affected by CVE-2026-12296?

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

Start Free Scan →Browse All CVEs