CVE-2026-31717

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 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/00ce8d6789dae72d042a4522264964c72891ca37	Patch
https://git.kernel.org/stable/c/49110a8ce654bbe56bef7c5e44cce31f4b102b8a	Patch
https://git.kernel.org/stable/c/712cdf917e77a6444ce3836874829d770db20ee6
https://git.kernel.org/stable/c/c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d
https://git.kernel.org/stable/c/c908c853f304a4969b5aa10eba0b50350cc65b80	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc1::::::

History

No history.

Information

Published : 2026-05-01 14:16

Updated : 2026-06-17 10:34

NVD link : CVE-2026-31717

Mitre link : CVE-2026-31717

CVE.ORG link : CVE-2026-31717

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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validate owner of durable handle on reconnect\n\nCurrently, ksmbd does not verify if the user attempting to reconnect\nto a durable handle is the same user who originally opened the file.\nThis allows any authenticated user to hijack an orphaned durable handle\nby predicting or brute-forcing the persistent ID.\n\nAccording to MS-SMB2, the server MUST verify that the SecurityContext\nof the reconnect request matches the SecurityContext associated with\nthe existing open.\nAdd a durable_owner structure to ksmbd_file to store the original opener's\nUID, GID, and account name. and catpure the owner information when a file\nhandle becomes orphaned. and implementing ksmbd_vfs_compare_durable_owner()\nto validate the identity of the requester during SMB2_CREATE (DHnC)."}], "lastModified": "2026-06-17T10:34:18.033", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": 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