CVE-2026-6753

HIGHPre-NVD 7.37.3—
EchelonGraph scoreMEDIUM confidence

Score 7.3 from GitHub Security Advisory (severity: HIGH) published 2026-04-21. NVD baseline CVSS 7.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
7.3
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.3Exploit: NoneExposed: 0

A fix is available — apply it.

Incorrect boundary conditions in the WebRTC component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

CVSS v3
7.3
EG Score
7.3(medium)
EG Risk
—
EPSS
22.8%
KEV
Not listed

Published

April 21, 2026

Last Modified

July 15, 2026

Advisory Details (5)

Auto-updated Jun 11, 2026
No patch confirmed yet.
generic

Security Vulnerabilities fixed in Thunderbird 140.10 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-34/
generic

Security Vulnerabilities fixed in Thunderbird 150 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-33/
generic

Security Vulnerabilities fixed in Firefox ESR 140.10 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-32/
generic

Security Vulnerabilities fixed in Firefox 150 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-30/
generic

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2027501

Vendor Advisories for CVE-2026-6753(20)

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

Patch Availability(27)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatfirefox-0:140.10.0-1.el8_42026-05-20redhat
redhatthunderbird-0:140.10.0-1.el10_02026-05-20redhat
redhatthunderbird-0:140.10.0-1.el8_82026-05-20redhat
redhatfirefox-0:140.10.0-1.el9_42026-05-20redhat
redhatthunderbird-0:140.10.0-1.el9_62026-05-20redhat
redhatthunderbird-0:140.10.0-1.el8_42026-05-20redhat
redhatfirefox-0:140.10.0-1.el8_62026-05-20redhat
redhatthunderbird-0:140.10.0-1.el9_22026-05-20redhat
redhatthunderbird-0:140.10.0-1.el8_62026-05-20redhat
redhatthunderbird-0:140.10.0-1.el9_02026-05-20redhat
redhatfirefox-0:140.10.0-2.el7_92026-05-20redhat
redhatthunderbird-0:140.10.0-1.el9_42026-05-20redhat
redhatfirefox-0:140.10.0-1.el10_22026-05-19redhat
redhatfirefox-0:140.10.0-1.el9_82026-05-19redhat
redhatthunderbird-0:140.10.0-1.el10_22026-05-19redhat
redhatthunderbird-0:140.10.1-1.el9_82026-05-19redhat
redhatfirefox-0:140.10.0-1.el9_02026-05-14redhat
redhatfirefox-0:140.10.0-1.el10_02026-05-14redhat
redhatfirefox-0:140.10.0-1.el8_82026-05-14redhat
redhatfirefox-0:140.10.0-1.el9_22026-05-14redhat
redhatfirefox-0:140.10.0-1.el9_62026-05-14redhat
redhatthunderbird-0:140.10.0-1.el9_72026-05-11redhat
redhatthunderbird-0:140.10.0-1.el8_102026-05-04redhat
redhatthunderbird-0:140.10.0-1.el10_12026-04-30redhat
redhatfirefox-0:140.10.0-1.el10_12026-04-27redhat
redhatfirefox-0:140.10.0-1.el9_72026-04-27redhat
redhatfirefox-0:140.10.0-1.el8_102026-04-27redhat

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.

Weakness Classification(2)

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

Additional Vendor Advisories

(7)

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 / 39× 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 123 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-6753?
CVE-2026-6753 is a high vulnerability published on April 21, 2026. Incorrect boundary conditions in the WebRTC component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
When was CVE-2026-6753 disclosed?
CVE-2026-6753 was first published in the National Vulnerability Database on April 21, 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-2026-6753 actively exploited?
CVE-2026-6753 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-2026-6753?
CVE-2026-6753 has a CVSS v3.1 base score of 7.3 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-6753?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-6753, 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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