CVE-2026-2765

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-02-24. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: None knownExposed: 0

A fix is available — apply it.

Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
59(Track)
EG Risk 59/100SSVC: 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
Severity98% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
40%
KEV
Not listed

Published

February 24, 2026

Last Modified

July 15, 2026

Advisory Details (10)

Auto-updated Sep 12, 2026
Patch available. Sources: redhat.
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.2 Advanced Update Support.

https://access.redhat.com/errata/RHSA-2026:3492
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.4 Extended Update Support

https://access.redhat.com/errata/RHSA-2026:3491
redhat Patch Available

Affected: Red Hat Enterprise Linux 10.

https://access.redhat.com/errata/RHSA-2026:3361
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:3339
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:3338
generic

Security Vulnerabilities fixed in Thunderbird 140.8 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-17/
generic

Security Vulnerabilities fixed in Thunderbird 148 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-16/
generic

Security Vulnerabilities fixed in Firefox ESR 140.8 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-15/
generic

Security Vulnerabilities fixed in Firefox 148 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-13/
generic

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2013562

Vendor Advisories for CVE-2026-2765(20)

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

Patch Availability(25)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatthunderbird-0:140.8.0-1.el8_22026-03-12redhat
redhatthunderbird-0:140.8.0-2.el10_02026-03-11redhat
redhatfirefox-0:140.8.0-2.el9_22026-03-10redhat
redhatfirefox-0:140.8.0-2.el7_92026-03-09redhat
redhatthunderbird-0:140.8.0-1.el8_82026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_22026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_02026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_62026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_42026-03-09redhat
redhatthunderbird-0:140.8.0-1.el8_62026-03-09redhat
redhatthunderbird-0:140.8.0-2.el8_42026-03-09redhat
redhatfirefox-0:140.8.0-2.el10_02026-03-09redhat
redhatthunderbird-0:140.8.0-2.el10_12026-03-02redhat
redhatthunderbird-0:140.8.0-1.el8_102026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_62026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_82026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_02026-03-02redhat
redhatthunderbird-0:140.8.0-1.el9_72026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_42026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_22026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_42026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_62026-03-02redhat
redhatfirefox-0:140.8.0-2.el10_12026-02-25redhat
redhatfirefox-0:140.8.0-2.el8_102026-02-25redhat
redhatfirefox-0:140.8.0-2.el9_72026-02-25redhat

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

(8 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
firefox-esr102.1.0esr-1 ... 91.9.1esr-1~deb9u1 (251 versions)140.8.0esr-1~deb11u1—
thunderbird1:102.0.1-1 ... 1:91.9.0-1~deb9u1 (302 versions)1:140.8.0esr-1~deb11u1—
Debian:12(2)
PackageVulnerable rangeFixed inDependents
firefox-esr102.11.0esr-1 ... 140.8.0esr-1~deb11u1 (158 versions)140.8.0esr-1~deb12u1—
thunderbird1:102.11.0-1 ... 1:140.8.0esr-1~deb11u1 (187 versions)1:140.8.0esr-1~deb12u1—
Debian:13(2)
PackageVulnerable rangeFixed inDependents
firefox-esr128.13.0esr-1 ... 140.8.0esr-1~deb12u1 (34 versions)140.8.0esr-1~deb13u1—
thunderbird1:128.13.0esr-1 ... 1:140.8.0esr-1~deb12u1 (43 versions)1:140.8.0esr-1~deb13u1—
Debian:14(2)
PackageVulnerable rangeFixed inDependents
firefox-esr128.13.0esr-1 ... 140.8.0esr-1~deb13u1 (35 versions)140.8.0esr-1—
thunderbird1:128.13.0esr-1 ... 1:140.8.0esr-1~deb13u1 (44 versions)1:140.8.0esr-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(5)

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 / 30× 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 251 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-2765?
CVE-2026-2765 is a critical vulnerability published on February 24, 2026. Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
When was CVE-2026-2765 disclosed?
CVE-2026-2765 was first published in the National Vulnerability Database on February 24, 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-2026-2765 actively exploited?
CVE-2026-2765 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 60.3% of all scored CVEs.
What is the CVSS score of CVE-2026-2765?
CVE-2026-2765 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-2765?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-2765, 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-2026-2765

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