CVE-2026-52944

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-06-24. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

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

ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE

FSCTL_SET_SPARSE in fsctl_set_sparse() modifies the file's sparse attribute and saves it through xattr without any permission checks.

This exposes two issues:

1) A client on a read-only share can change the sparse attribute on files it opened, even though the share is read-only. Other FSCTL write operations already check test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE), but FSCTL_SET_SPARSE does not.

2) Even on writable shares, clients without FILE_WRITE_DATA or FILE_WRITE_ATTRIBUTES access should not modify the sparse attribute. Similar handle-level checks exist in other functions but are missing here.

Add both share-level writable check and per-handle access check. Use goto out on error to avoid leaking file references.

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: 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
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
2%
KEV
Not listed

Published

June 24, 2026

Last Modified

July 8, 2026

Advisory Details (4)

Auto-updated Jul 8, 2026
No patch confirmed yet.
generic

ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/de9eb0b44fa9123170e6245b49638e0e453c10f8
generic

ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/cc57232cae23c0df91b4a59d0f519141ce9b5b02
generic

ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/aef151bcfa494bfe983669de2726734b534adb73
generic

ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/3127a884525dc8ca4def73254bfcd3ccef0bf812

Vendor Advisories for CVE-2026-52944(2)

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

Patch Availability(8)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-28.28) @ resolute2026-08-30ubuntu
ubuntulinux-tools-oem-7.0 (7.0.0-1009.9) @ resolute2026-08-30ubuntu
ubuntulinux-virtual-hwe-24.04-edge (7.0.0-28.28~24.04.1) @ noble2026-08-30ubuntu
ubuntulinux-tools-oracle-7.0 (7.0.0-1008.8) @ resolute2026-08-30ubuntu
ubuntulinux-tools-azure-fde-7.0 (7.0.0-1009.9) @ resolute2026-08-30ubuntu
ubuntulinux-tools-raspi-realtime-7.0 (7.0.0-1015.15) @ resolute2026-08-30ubuntu
ubuntulinux-tools-nvidia-hwe-24.04-edge (7.0.0-1016.16) @ resolute2026-08-30ubuntu
ubuntulinux-tools-nvidia-hwe-26.04 (7.0.0-2016.16) @ resolute2026-08-30ubuntu

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

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 7.2~rc7-1~exp1 (350 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (174 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.0.9-1~bpo13+1 (141 versions)7.0.12-1—

Additional Vendor Advisories

(8)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 5× in last 7d / 64× 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 186 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-52944?
CVE-2026-52944 is a medium vulnerability published on June 24, 2026. In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTLSETSPARSE FSCTLSETSPARSE in fsctlsetsparse() modifies the file's sparse attribute and saves it through xattr without any permission checks. This exposes two…
When was CVE-2026-52944 disclosed?
CVE-2026-52944 was first published in the National Vulnerability Database on June 24, 2026, with the most recent update on July 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-52944 actively exploited?
CVE-2026-52944 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 97.8% of all scored CVEs.
What is the CVSS score of CVE-2026-52944?
CVE-2026-52944 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-52944?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-52944, 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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