CVE-2026-39877

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-07-27. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: None knownExposed: 0

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

A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 18.7.10 and iPadOS 18.7.10, iOS 26.5 and iPadOS 26.5, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.5, tvOS 26.5, visionOS 26.5, watchOS 26.5. An app may be able to disclose kernel memory.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: 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
Severity78% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
9%
KEV
Not listed

Published

July 27, 2026

Last Modified

August 25, 2026

Advisory Details (2)

Auto-updated Jul 28, 2026
No patch confirmed yet.
generic

About the security content of macOS Sonoma 14.8.8 - Apple Support

https://support.apple.com/en-us/128072
generic

About the security content of macOS Sequoia 15.7.8 - Apple Support

https://support.apple.com/en-us/128071

Vendor Advisories for CVE-2026-39877(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 21× in last 7d / 112× 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 132 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-39877?
CVE-2026-39877 is a high vulnerability published on July 27, 2026. A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 18.7.10 and iPadOS 18.7.10, iOS 26.5 and iPadOS 26.5, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.5, tvOS 26.5, visionOS 26.5, watchOS 26.5. An app may be able to disclose kernel memory.
When was CVE-2026-39877 disclosed?
CVE-2026-39877 was first published in the National Vulnerability Database on July 27, 2026, with the most recent update on August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-39877 actively exploited?
CVE-2026-39877 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 90.5% of all scored CVEs.
What is the CVSS score of CVE-2026-39877?
CVE-2026-39877 has a CVSS v3.1 base score of 7.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-39877?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-39877, 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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