CVE-2026-64395

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-25. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

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

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: require source read access for duplicate extents

FSCTL_DUPLICATE_EXTENTS_TO_FILE passes the source file directly to vfs_clone_file_range() or vfs_copy_file_range() without checking the SMB access mask granted to the source handle. A handle opened with attribute access can consequently be used to copy file contents into an attacker-readable destination.

Require FILE_READ_DATA on the source handle before either VFS operation, matching other ksmbd data-copy paths.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: 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
Severity75% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
34%
KEV
Not listed

Published

July 25, 2026

Last Modified

August 17, 2026

Advisory Details (6)

Auto-updated Jul 27, 2026
No patch confirmed yet.
generic

ksmbd: require source read access for duplicate extents - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/db231af842868268839f9f9619c68cb27830d8be
generic

ksmbd: require source read access for duplicate extents - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/cedff600f1642aa982178503552f0d007bc829c8
generic

ksmbd: require source read access for duplicate extents - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f
generic

ksmbd: require source read access for duplicate extents - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a10942af27832c2761d020863a46e79bebe0567d
generic

ksmbd: require source read access for duplicate extents - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/67bdad9cf01b25030e3bf00bbce6c309319d6663
generic

ksmbd: require source read access for duplicate extents - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2d2ab6983620c2d60ce7db72133984ca3873b929

Vendor Advisories for CVE-2026-64395(2)

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

Affected Packages

(5 across 4 ecosystems)
Debian:12(2)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (55 versions)6.1.180-1—
linux-6.12—6.12.100-1~deb12u1—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux-6.16.1.106-3~deb11u1 ... 6.1.177-1~deb11u1 (22 versions)6.1.180-1~deb11u1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.95-1~bpo12+1 (30 versions)6.12.96-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.1~rc7-1~exp1 (156 versions)7.1.4-1—

Data Freshness Timeline

(refreshed 19× in last 7d / 114× 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 146 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-64395?
CVE-2026-64395 is a high vulnerability published on July 25, 2026. In the Linux kernel, the following vulnerability has been resolved: ksmbd: require source read access for duplicate extents FSCTLDUPLICATEEXTENTSTOFILE passes the source file directly to vfsclonefilerange() or vfscopyfilerange() without checking the SMB access mask granted to the source handle. A…
When was CVE-2026-64395 disclosed?
CVE-2026-64395 was first published in the National Vulnerability Database on July 25, 2026, with the most recent update on August 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-64395 actively exploited?
CVE-2026-64395 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 66.4% of all scored CVEs.
What is the CVSS score of CVE-2026-64395?
CVE-2026-64395 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-64395?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-64395, 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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