CVE-2025-40039

MEDIUMNVD 4.74.7—
EchelonGraph scoreMEDIUM confidence

Score 4.7 from GitHub Security Advisory published 2025-10-28. NVD baseline CVSS 4.7; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
4.7EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.7Exploit: None knownExposed: 0

A fix is available — apply it.

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

ksmbd: Fix race condition in RPC handle list access

The 'sess->rpc_handle_list' XArray manages RPC handles within a ksmbd session. Access to this list is intended to be protected by 'sess->rpc_lock' (an rw_semaphore). However, the locking implementation was flawed, leading to potential race conditions.

In ksmbd_session_rpc_open(), the code incorrectly acquired only a read lock before calling xa_store() and xa_erase(). Since these operations modify the XArray structure, a write lock is required to ensure exclusive access and prevent data corruption from concurrent modifications.

Furthermore, ksmbd_session_rpc_method() accessed the list using xa_load() without holding any lock at all. This could lead to reading inconsistent data or a potential use-after-free if an entry is concurrently removed and the pointer is dereferenced.

Fix these issues by:

  • Using down_write() and up_write() in ksmbd_session_rpc_open()
to ensure exclusive access during XArray modification, and ensuring the lock is correctly released on error paths.
  • Adding down_read() and up_read() in ksmbd_session_rpc_method()
to safely protect the lookup.

CVSS v3
4.7
EG Score
4.7(medium)
EG Risk
26(Track)
EG Risk 26/100SSVC: 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
Severity47% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
23%
KEV
Not listed

Published

October 28, 2025

Last Modified

August 5, 2026

Advisory Details (5)

Auto-updated Aug 5, 2026
No patch confirmed yet.
generic

ksmbd: Fix race condition in RPC handle list access - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/305853cce379407090a73b38c5de5ba748893aee
generic

ksmbd: Fix race condition in RPC handle list access - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6bd7e0e55dcea2cf0d391bbc21c2eb069b4be3e1
generic

ksmbd: Fix race condition in RPC handle list access - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5cc679ba0f4505936124cd4179ba66bb0a4bd9f3
generic

ksmbd: Fix race condition in RPC handle list access - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6b615a8fb3af0baf8126cde3d4fee97d57222ffc
generic

ksmbd: Fix race condition in RPC handle list access - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/69674b029002b1d90b655f014bdf64f404efa54d

Patch Availability(12)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-hwe-24.04-edge (6.17.0-14.14) @ questing2026-05-27ubuntu
ubuntulinux-tools-oracle-64k-6.17 (6.17.0-1007.7) @ questing2026-05-27ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1056.62) @ noble2026-05-27ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1054.57.1) @ noble2026-05-27ubuntu
ubuntulinux-tools-oem-6.17 (6.17.0-1011.11) @ noble2026-05-27ubuntu
ubuntulinux-tools-gcp-64k-6.17 (6.17.0-1007.7) @ questing2026-05-27ubuntu
ubuntulinux-tools-nvidia-tegra-rt-6.8 (6.8.0-1024.24) @ noble2026-05-27ubuntu
ubuntulinux-tools-nvidia-hwe-22.04-edge (6.8.0-1054.57~22.04.1) @ jammy2026-05-27ubuntu
ubuntulinux-tools-azure-6.17 (6.17.0-1008.8) @ questing2026-05-27ubuntu
ubuntulinux-virtual-6.8 (6.8.0-117.117) @ noble2026-05-27ubuntu
ubuntulinux-tools-fips-6.8 (6.8.0-116.116+fips1) @ noble2026-05-27ubuntu
linuxKernel @ 6.6.123—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.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux-6.16.1.106-3~deb11u1 ... 6.1.159-1~deb11u1 (14 versions)6.1.162-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (46 versions)6.1.162-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.57-1~bpo12+1 (6 versions)6.12.57-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.17.5-1~exp1 (75 versions)6.17.6-1—

Weakness Classification(1)

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

All Vendor Advisories

(15)

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 5× in last 7d / 25× 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 156 total refreshes for this CVE.

  1. 2026-09-20 20:15 UTCEPSS rescore
  2. 2026-09-18 19:27 UTCEPSS rescore
  3. 2026-09-17 19:29 UTCEPSS rescore
  4. 2026-09-16 14:07 UTCEPSS rescore
  5. 2026-09-16 05:14 UTCEPSS rescore
  6. 2026-09-13 16:46 UTCEPSS rescore
  7. 2026-09-12 15:00 UTCEPSS rescore
  8. 2026-09-11 14:52 UTCEPSS rescore
  9. 2026-09-11 09:35 UTCEPSS rescore
  10. 2026-09-10 09:33 UTCEPSS rescore
  11. 2026-09-08 21:59 UTCEPSS rescore
  12. 2026-09-07 16:00 UTCEPSS rescore
  13. 2026-09-07 11:18 UTCOSV refresh
  14. 2026-09-06 13:46 UTCEPSS rescore
  15. 2026-09-04 05:05 UTCEPSS rescore
  16. 2026-09-02 14:11 UTCEPSS rescore
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 04:38 UTCEPSS rescore
  19. 2026-08-30 19:16 UTCEPSS rescore
  20. 2026-08-30 01:21 UTCEPSS rescore
  21. 2026-08-28 21:40 UTCEPSS rescore
  22. 2026-08-27 14:24 UTCEPSS rescore
  23. 2026-08-26 14:45 UTCEPSS rescore
  24. 2026-08-25 13:48 UTCEPSS rescore
  25. 2026-08-23 00:18 UTCEPSS rescore
Show 75 more
  1. 2026-08-21 23:48 UTCEPSS rescore
  2. 2026-08-20 22:54 UTCEPSS rescore
  3. 2026-08-20 20:31 UTCOSV refresh
  4. 2026-08-19 17:03 UTCEPSS rescore
  5. 2026-08-19 17:03 UTCEPSS rescore
  6. 2026-08-18 13:47 UTCEPSS rescore
  7. 2026-08-17 13:46 UTCEPSS rescore
  8. 2026-08-16 14:55 UTCEPSS rescore
  9. 2026-08-16 02:13 UTCEPSS rescore
  10. 2026-08-15 01:29 UTCEPSS rescore
  11. 2026-08-13 21:59 UTCEPSS rescore
  12. 2026-08-12 13:50 UTCEPSS rescore
  13. 2026-08-09 13:46 UTCEPSS rescore
  14. 2026-08-08 16:36 UTCEPSS rescore
  15. 2026-08-07 16:26 UTCEPSS rescore
  16. 2026-08-06 13:46 UTCEPSS rescore
  17. 2026-08-05 12:53 UTCEG score recompute
  18. 2026-08-05 12:53 UTCVendor advisory
  19. 2026-08-05 12:53 UTCGHSA enrichment
  20. 2026-08-04 15:09 UTCEPSS rescore
  21. 2026-08-04 10:37 UTCEPSS rescore
  22. 2026-08-03 10:35 UTCEPSS rescore
  23. 2026-08-02 02:26 UTCEPSS rescore
  24. 2026-08-01 04:15 UTCEPSS rescore
  25. 2026-07-30 16:27 UTCEPSS rescore
  26. 2026-07-30 06:49 UTCEG score recompute
  27. 2026-07-30 06:49 UTCVendor advisory
  28. 2026-07-30 06:49 UTCGHSA enrichment
  29. 2026-07-30 06:24 UTCNVD updateCVSS v3 → 4.7 · severity → MEDIUM
  30. 2026-07-30 06:18 UTCMITRE cvelistV5CVSS v3 → 8.8 · severity → HIGH
  31. 2026-07-30 01:29 UTCEPSS rescore
  32. 2026-07-28 15:35 UTCEPSS rescore
  33. 2026-07-26 14:54 UTCEPSS rescore
  34. 2026-07-24 14:17 UTCEPSS rescore
  35. 2026-07-23 02:55 UTCEG score recompute
  36. 2026-07-22 14:07 UTCEPSS rescore
  37. 2026-07-22 14:07 UTCEPSS rescore
  38. 2026-07-21 15:24 UTCEPSS rescore
  39. 2026-07-20 17:07 UTCEPSS rescore
  40. 2026-07-20 00:08 UTCOSV refresh
  41. 2026-07-19 14:30 UTCEPSS rescore
  42. 2026-07-19 14:30 UTCEPSS rescore
  43. 2026-07-19 02:28 UTCEPSS rescore
  44. 2026-07-19 02:28 UTCEPSS rescore
  45. 2026-07-18 10:04 UTCEPSS rescore
  46. 2026-07-18 10:04 UTCEPSS rescore
  47. 2026-07-16 17:02 UTCEPSS rescore
  48. 2026-07-15 16:57 UTCEPSS rescore
  49. 2026-07-15 16:57 UTCEPSS rescore
  50. 2026-07-15 01:59 UTCEPSS rescore
  51. 2026-07-15 01:59 UTCEPSS rescore
  52. 2026-07-13 22:29 UTCEPSS rescore
  53. 2026-07-13 22:29 UTCEPSS rescore
  54. 2026-07-13 06:12 UTCEPSS rescore
  55. 2026-07-12 05:46 UTCEPSS rescore
  56. 2026-07-11 08:27 UTCEPSS rescore
  57. 2026-07-11 08:27 UTCEPSS rescore
  58. 2026-07-09 19:09 UTCEPSS rescore
  59. 2026-07-09 19:09 UTCEPSS rescore
  60. 2026-07-07 13:45 UTCEPSS rescore
  61. 2026-07-06 16:27 UTCEPSS rescore
  62. 2026-07-06 16:27 UTCEPSS rescore
  63. 2026-07-05 02:30 UTCEPSS rescore
  64. 2026-07-02 15:00 UTCOSV refresh
  65. 2026-07-01 15:06 UTCEPSS rescore
  66. 2026-07-01 15:06 UTCEPSS rescore
  67. 2026-06-30 23:22 UTCEPSS rescore
  68. 2026-06-30 23:22 UTCEPSS rescore
  69. 2026-06-29 14:06 UTCEPSS rescore
  70. 2026-06-29 14:06 UTCEPSS rescore
  71. 2026-06-28 14:07 UTCEPSS rescore
  72. 2026-06-28 14:07 UTCEPSS rescore
  73. 2026-06-28 04:55 UTCEPSS rescore
  74. 2026-06-28 04:55 UTCEPSS rescore
  75. 2026-06-27 03:08 UTCEPSS rescore

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Frequently asked(5)

What is CVE-2025-40039?
CVE-2025-40039 is a medium vulnerability published on October 28, 2025. In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix race condition in RPC handle list access The 'sess->rpchandlelist' XArray manages RPC handles within a ksmbd session. Access to this list is intended to be protected by 'sess->rpclock' (an rwsemaphore). However, the…
When was CVE-2025-40039 disclosed?
CVE-2025-40039 was first published in the National Vulnerability Database on October 28, 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-2025-40039 actively exploited?
CVE-2025-40039 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 77.0% of all scored CVEs.
What is the CVSS score of CVE-2025-40039?
CVE-2025-40039 has a CVSS v3 base score of 4.7 (NVD).
How do I remediate CVE-2025-40039?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-40039, 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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