CVE-2025-40285

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2025-12-07. the CNA's CVSS baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:linux, epss, ghsa
Trending — 5 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

A fix is available — apply it.

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

smb/server: fix possible refcount leak in smb2_sess_setup()

Reference count of ksmbd_session will leak when session need reconnect. Fix this by adding the missing ksmbd_user_session_put().

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
33%
KEV
Not listed

Published

December 6, 2025

Last Modified

August 5, 2026

Advisory Details (5)

Auto-updated Jul 31, 2026
No patch confirmed yet.
generic

smb/server: fix possible refcount leak in smb2_sess_setup() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e671f9bb97805771380c98de944e2ceab6949188
generic

smb/server: fix possible refcount leak in smb2_sess_setup() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/dcc51dfe6ff26b52cac106865a172ac982d78401
generic

smb/server: fix possible refcount leak in smb2_sess_setup() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d37b2c81c83d6c0d5ca582f4fe73c672983f9e0d
generic

smb/server: fix possible refcount leak in smb2_sess_setup() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6fc935f798d44a8eb8a5e6659198399fbf57b981
generic

smb/server: fix possible refcount leak in smb2_sess_setup() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/379510a815cb2e64eb0a379cb62295d6ade65df0

Vendor Advisories for CVE-2025-40285(1)

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

Patch Availability(16)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-hwe-24.04-edge (6.17.0-14.14) @ questing2026-05-21ubuntu
ubuntulinux-tools-gcp-64k-6.17 (6.17.0-1007.7) @ questing2026-05-21ubuntu
ubuntulinux-tools-oracle-64k-6.17 (6.17.0-1007.7) @ questing2026-05-21ubuntu
ubuntulinux-tools-oem-6.17 (6.17.0-1011.11) @ noble2026-05-21ubuntu
ubuntulinux-tools-azure-6.17 (6.17.0-1008.8) @ questing2026-05-21ubuntu
ubuntulinux-virtual-6.8 (6.8.0-106.106) @ noble2026-05-21ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1052.58+fips1) @ noble2026-05-21ubuntu
ubuntulinux-tools-aws-edge (6.8.0-1050.53~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1051.57) @ noble2026-05-21ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1049.52.1) @ noble2026-05-21ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1052.55+fips1) @ noble2026-05-21ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2040.41) @ noble2026-05-21ubuntu
ubuntulinux-tools-realtime-6.8.1 (6.8.1-1045.46) @ noble2026-05-21ubuntu
ubuntulinux-tools-azure-edge (6.8.0-1051.57~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-xilinx-zynqmp (6.8.0.1029.30) @ noble2026-05-21ubuntu
linuxKernel @ 6.1.159—osv

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.

All Vendor Advisories

(16)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 13× in last 7d / 46× 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 140 total refreshes for this CVE.

  1. 2026-08-05 12:51 UTCEG score recompute
  2. 2026-08-05 12:51 UTCVendor advisory
  3. 2026-08-05 12:50 UTCGHSA enrichment
  4. 2026-08-04 15:09 UTCEPSS rescore
  5. 2026-08-04 10:37 UTCEPSS rescore
  6. 2026-08-03 10:35 UTCEPSS rescore
  7. 2026-08-02 02:26 UTCEPSS rescore
  8. 2026-08-01 04:15 UTCEPSS rescore
  9. 2026-07-30 16:27 UTCEPSS rescore
  10. 2026-07-30 06:25 UTCEG score recompute▲ 7.50
  11. 2026-07-30 06:25 UTCVendor advisory
  12. 2026-07-30 06:25 UTCGHSA enrichment
  13. 2026-07-30 06:18 UTCMITRE cvelistV5CVSS v3 → 7.5 · severity → HIGH
  14. 2026-07-30 01:29 UTCEPSS rescore
  15. 2026-07-28 15:35 UTCEPSS rescore
  16. 2026-07-27 06:09 UTCOSV refresh
  17. 2026-07-26 14:54 UTCEPSS rescore
  18. 2026-07-25 14:17 UTCEPSS rescore
  19. 2026-07-25 14:17 UTCEPSS rescore
  20. 2026-07-24 14:17 UTCEPSS rescore
  21. 2026-07-23 02:55 UTCEG score recompute
  22. 2026-07-22 14:07 UTCEPSS rescore
  23. 2026-07-22 14:07 UTCEPSS rescore
  24. 2026-07-21 15:24 UTCEPSS rescore
  25. 2026-07-20 17:07 UTCEPSS rescore
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  1. 2026-07-19 14:30 UTCEPSS rescore
  2. 2026-07-19 14:30 UTCEPSS rescore
  3. 2026-07-19 02:28 UTCEPSS rescore
  4. 2026-07-19 02:28 UTCEPSS rescore
  5. 2026-07-18 10:04 UTCEPSS rescore
  6. 2026-07-18 10:04 UTCEPSS rescore
  7. 2026-07-16 17:02 UTCEPSS rescore
  8. 2026-07-15 16:57 UTCEPSS rescore
  9. 2026-07-15 16:57 UTCEPSS rescore
  10. 2026-07-15 01:59 UTCEPSS rescore
  11. 2026-07-15 01:59 UTCEPSS rescore
  12. 2026-07-13 22:29 UTCEPSS rescore
  13. 2026-07-13 22:29 UTCEPSS rescore
  14. 2026-07-13 06:12 UTCEPSS rescore
  15. 2026-07-12 05:46 UTCEPSS rescore
  16. 2026-07-11 08:27 UTCEPSS rescore
  17. 2026-07-11 08:27 UTCEPSS rescore
  18. 2026-07-10 00:47 UTCOSV refresh
  19. 2026-07-09 19:09 UTCEPSS rescore
  20. 2026-07-09 19:09 UTCEPSS rescore
  21. 2026-07-07 13:45 UTCEPSS rescore
  22. 2026-07-06 16:27 UTCEPSS rescore
  23. 2026-07-06 16:27 UTCEPSS rescore
  24. 2026-07-06 02:23 UTCEPSS rescore
  25. 2026-07-05 02:30 UTCEPSS rescore
  26. 2026-07-04 06:30 UTCEPSS rescore
  27. 2026-07-01 15:06 UTCEPSS rescore
  28. 2026-07-01 15:06 UTCEPSS rescore
  29. 2026-06-30 23:22 UTCEPSS rescore
  30. 2026-06-30 23:22 UTCEPSS rescore
  31. 2026-06-29 14:06 UTCEPSS rescore
  32. 2026-06-29 14:06 UTCEPSS rescore
  33. 2026-06-28 14:07 UTCEPSS rescore
  34. 2026-06-28 14:07 UTCEPSS rescore
  35. 2026-06-28 04:55 UTCEPSS rescore
  36. 2026-06-28 04:55 UTCEPSS rescore
  37. 2026-06-27 03:08 UTCEPSS rescore
  38. 2026-06-27 03:08 UTCEPSS rescore
  39. 2026-06-25 13:49 UTCEPSS rescore
  40. 2026-06-25 13:49 UTCEPSS rescore
  41. 2026-06-24 14:04 UTCEPSS rescore
  42. 2026-06-24 14:04 UTCEPSS rescore
  43. 2026-06-23 21:32 UTCEPSS rescore
  44. 2026-06-23 21:32 UTCEPSS rescore
  45. 2026-06-22 14:25 UTCEPSS rescore
  46. 2026-06-22 14:25 UTCEPSS rescore
  47. 2026-06-21 14:56 UTCEPSS rescore
  48. 2026-06-21 14:56 UTCEPSS rescore
  49. 2026-06-21 11:31 UTCOSV refresh
  50. 2026-06-21 01:59 UTCEPSS rescore
  51. 2026-06-21 01:59 UTCEPSS rescore
  52. 2026-06-19 19:25 UTCEPSS rescore
  53. 2026-06-19 19:25 UTCEPSS rescore
  54. 2026-06-18 17:52 UTCEPSS rescore
  55. 2026-06-18 17:52 UTCEPSS rescore
  56. 2026-06-17 17:52 UTCEPSS rescore
  57. 2026-06-16 17:52 UTCEPSS rescore
  58. 2026-06-16 17:52 UTCEPSS rescore
  59. 2026-06-14 23:17 UTCEPSS rescore
  60. 2026-06-13 23:00 UTCEPSS rescore
  61. 2026-06-12 23:11 UTCEPSS rescore
  62. 2026-06-11 14:00 UTCEPSS rescore
  63. 2026-06-10 22:18 UTCEPSS rescore
  64. 2026-06-10 13:22 UTCEPSS rescore
  65. 2026-06-08 14:16 UTCEPSS rescore
  66. 2026-06-08 14:16 UTCEPSS rescore
  67. 2026-06-07 15:24 UTCEPSS rescore
  68. 2026-06-06 13:47 UTCEPSS rescore
  69. 2026-06-06 13:47 UTCEPSS rescore
  70. 2026-06-05 22:46 UTCEPSS rescore
  71. 2026-06-05 22:46 UTCEPSS rescore
  72. 2026-06-05 06:10 UTCEPSS rescore
  73. 2026-06-05 06:10 UTCEPSS rescore
  74. 2026-06-02 20:12 UTCEPSS rescore
  75. 2026-06-02 03:09 UTCOSV refresh

Frequently asked(5)

What is CVE-2025-40285?
CVE-2025-40285 is a high vulnerability published on December 6, 2025. In the Linux kernel, the following vulnerability has been resolved: smb/server: fix possible refcount leak in smb2sesssetup() Reference count of ksmbd_session will leak when session need reconnect. Fix this by adding the missing ksmbdusersession_put().
When was CVE-2025-40285 disclosed?
CVE-2025-40285 was first published in the National Vulnerability Database on December 6, 2025, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2025-40285 actively exploited?
CVE-2025-40285 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 66.7% of all scored CVEs.
What is the CVSS score of CVE-2025-40285?
CVE-2025-40285 has a CVSS v4.0 base score of 7.5 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2025-40285?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-40285, 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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