CVE-2026-54257

CRITICALPre-NVD 9.39.3—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 83% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
9.3
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 9.3Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. From 42.3.1 until 42.3.3, Buffer performs incorrect byte length calculations resulting in heap buffer under/overflow. Most apps will crash and some may perform incorrect buffer allocations in the Node.js Buffer API resulting in unexpected truncation or allocation. This vulnerability is fixed in 42.3.3.

CVSS v3
9.3
EG Score
9.3(medium)
EPSS
16.6%
KEV
Not listed

Published

June 15, 2026

Last Modified

June 25, 2026

Advisory Details (1)

Auto-updated Jun 23, 2026
Patch available. Sources: github.
github Patch Available

Buffer performs incorrect byte length calculations resulting in heap buffer under/overflow · Advisory · electron/electron · GitHub

https://github.com/electron/electron/security/advisories/GHSA-q6m5-f73j-m9mc

Vendor Advisories for CVE-2026-54257(1)

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

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
electron—42.3.3—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 41× in last 7d / 86× 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. 2026-07-07 04:53 UTCEG score recompute
  2. 2026-07-07 00:16 UTCEG score recompute
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 07:22 UTCEG score recompute
  6. 2026-07-06 02:45 UTCEG score recompute
  7. 2026-07-06 02:23 UTCEPSS rescore
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  9. 2026-07-05 22:24 UTCEG score recompute
  10. 2026-07-05 18:01 UTCEG score recompute
  11. 2026-07-05 13:43 UTCEG score recompute
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  13. 2026-07-05 02:31 UTCEPSS rescore
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  15. 2026-07-04 23:19 UTCEG score recompute
  16. 2026-07-04 18:58 UTCEG score recompute
  17. 2026-07-04 14:17 UTCEG score recompute
  18. 2026-07-04 09:58 UTCEG score recompute
  19. 2026-07-04 06:31 UTCEPSS rescore
  20. 2026-07-04 06:31 UTCEPSS rescore
  21. 2026-07-03 22:52 UTCEG score recompute
  22. 2026-07-03 18:34 UTCEG score recompute
  23. 2026-07-03 14:14 UTCEG score recompute
  24. 2026-07-03 07:15 UTCEG score recompute
  25. 2026-07-03 01:41 UTCEG score recompute
Show 61 more
  1. 2026-07-02 21:21 UTCEG score recompute
  2. 2026-07-02 17:02 UTCEG score recompute
  3. 2026-07-02 12:42 UTCEG score recompute
  4. 2026-07-02 08:23 UTCEG score recompute
  5. 2026-07-02 04:04 UTCEG score recompute
  6. 2026-07-01 23:44 UTCEG score recompute
  7. 2026-07-01 19:24 UTCEG score recompute
  8. 2026-07-01 15:07 UTCEPSS rescore
  9. 2026-07-01 15:06 UTCEG score recompute
  10. 2026-07-01 10:47 UTCEG score recompute
  11. 2026-07-01 06:27 UTCEG score recompute
  12. 2026-07-01 02:08 UTCEG score recompute
  13. 2026-06-30 23:22 UTCEPSS rescore
  14. 2026-06-30 21:48 UTCEG score recompute
  15. 2026-06-30 17:29 UTCEG score recompute
  16. 2026-06-30 12:57 UTCEG score recompute
  17. 2026-06-30 07:31 UTCEG score recompute
  18. 2026-06-30 03:11 UTCEG score recompute
  19. 2026-06-29 22:52 UTCEG score recompute
  20. 2026-06-29 18:34 UTCEG score recompute
  21. 2026-06-29 14:06 UTCEPSS rescore
  22. 2026-06-29 14:06 UTCEPSS rescore
  23. 2026-06-29 13:27 UTCEG score recompute
  24. 2026-06-29 09:09 UTCEG score recompute
  25. 2026-06-29 04:51 UTCEG score recompute
  26. 2026-06-29 00:30 UTCEG score recompute
  27. 2026-06-28 20:10 UTCEG score recompute
  28. 2026-06-28 15:51 UTCEG score recompute
  29. 2026-06-28 14:07 UTCEPSS rescore
  30. 2026-06-28 11:32 UTCEG score recompute
  31. 2026-06-28 07:13 UTCEG score recompute
  32. 2026-06-28 04:56 UTCEPSS rescore
  33. 2026-06-28 04:56 UTCEPSS rescore
  34. 2026-06-28 02:46 UTCEG score recompute
  35. 2026-06-27 22:27 UTCEG score recompute
  36. 2026-06-27 18:08 UTCEG score recompute
  37. 2026-06-27 13:50 UTCEG score recompute
  38. 2026-06-27 09:31 UTCEG score recompute
  39. 2026-06-27 05:12 UTCEG score recompute
  40. 2026-06-27 03:08 UTCEPSS rescore
  41. 2026-06-27 00:52 UTCEG score recompute
  42. 2026-06-26 20:34 UTCEG score recompute
  43. 2026-06-26 16:15 UTCEG score recompute
  44. 2026-06-26 11:57 UTCEG score recompute
  45. 2026-06-26 02:43 UTCEG score recompute
  46. 2026-06-25 22:24 UTCEG score recompute
  47. 2026-06-25 18:04 UTCEG score recompute
  48. 2026-06-25 13:49 UTCEPSS rescore
  49. 2026-06-25 13:46 UTCEG score recompute
  50. 2026-06-25 09:27 UTCEG score recompute
  51. 2026-06-25 05:09 UTCEG score recompute
  52. 2026-06-25 00:45 UTCEG score recompute
  53. 2026-06-24 20:25 UTCEG score recompute
  54. 2026-06-24 14:05 UTCEPSS rescore
  55. 2026-06-24 13:21 UTCEG score recompute
  56. 2026-06-24 08:38 UTCEG score recompute
  57. 2026-06-24 04:19 UTCEG score recompute
  58. 2026-06-24 00:01 UTCEG score recompute
  59. 2026-06-23 19:35 UTCEG score recompute▲ 9.30
  60. 2026-06-23 19:32 UTCNVD updateCVSS v3 → 9.3 · CVSS v4 → 9.3
  61. 2026-06-15 20:46 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-54257?
CVE-2026-54257 is a critical vulnerability published on June 15, 2026. Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. From 42.3.1 until 42.3.3, Buffer performs incorrect byte length calculations resulting in heap buffer under/overflow. Most apps will crash and some may perform incorrect buffer allocations in the…
When was CVE-2026-54257 disclosed?
CVE-2026-54257 was first published in the National Vulnerability Database on June 15, 2026, with the most recent update on June 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-54257 actively exploited?
CVE-2026-54257 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 16.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-54257?
CVE-2026-54257 has a CVSS v3 base score of 9.3 (NVD).
How do I remediate CVE-2026-54257?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-54257, 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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