CVE-2026-31717

HIGHPre-NVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-05-01. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
8.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.8Exploit: NoneExposed: 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: validate owner of durable handle on reconnect

Currently, ksmbd does not verify if the user attempting to reconnect to a durable handle is the same user who originally opened the file. This allows any authenticated user to hijack an orphaned durable handle by predicting or brute-forcing the persistent ID.

According to MS-SMB2, the server MUST verify that the SecurityContext of the reconnect request matches the SecurityContext associated with the existing open. Add a durable_owner structure to ksmbd_file to store the original opener's UID, GID, and account name. and catpure the owner information when a file handle becomes orphaned. and implementing ksmbd_vfs_compare_durable_owner() to validate the identity of the requester during SMB2_CREATE (DHnC).

CVSS v3
8.8
EG Score
8.8(medium)
EPSS
35.4%
KEV
Not listed

Published

May 1, 2026

Last Modified

June 14, 2026

Advisory Details (3)

Auto-updated May 3, 2026
No patch confirmed yet.
generic

ksmbd: validate owner of durable handle on reconnect - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c908c853f304a4969b5aa10eba0b50350cc65b80
generic

ksmbd: validate owner of durable handle on reconnect - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/49110a8ce654bbe56bef7c5e44cce31f4b102b8a
generic

ksmbd: validate owner of durable handle on reconnect - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/00ce8d6789dae72d042a4522264964c72891ca37

Vendor Advisories for CVE-2026-31717(2)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 43× 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 149 total refreshes for this CVE.

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

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCTurtleARM/CVE-2026-31717-KSMBD-Exploit
    First seen May 4, 2026
    Open source ↗

Frequently asked(5)

What is CVE-2026-31717?
CVE-2026-31717 is a high vulnerability published on May 1, 2026. In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate owner of durable handle on reconnect Currently, ksmbd does not verify if the user attempting to reconnect to a durable handle is the same user who originally opened the file. This allows any authenticated user to…
When was CVE-2026-31717 disclosed?
CVE-2026-31717 was first published in the National Vulnerability Database on May 1, 2026, with the most recent update on June 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31717 actively exploited?
CVE-2026-31717 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 35.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-31717?
CVE-2026-31717 has a CVSS v4.0 base score of 8.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-31717?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31717, 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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