CVE-2026-68457

In the Linux kernel, the following vulnerability has been resolved: ksmbd: use opener credentials for FSCTL mutations SET_SPARSE, SET_ZERO_DATA and SET_COMPRESSION operate on an open SMB handle but call VFS xattr, fallocate or fileattr helpers with the current ksmbd worker credentials. Those helpers can revalidate inode permissions, ownership and LSM policy independently of the SMB handle access mask. Run each operation with the credentials captured in the target file when the handle was opened. Keep credential handling local to these single-file FSCTLs rather than applying session credentials to the complete IOCTL handler, which also contains handle-less and multi-handle operations.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1e112c47ec5dd1942e2d4ca6e8e9b712238e20c2
https://git.kernel.org/stable/c/a8c18434e1f0d9f7989170bdb0490c0160baf065
https://git.kernel.org/stable/c/c6394bcaf254c5baf9aff43376020be5db6d3316
https://git.kernel.org/stable/c/cfb2c6f71d61ed807c9d7a7af331d406f1f31877
https://git.kernel.org/stable/c/e205f3e7e8c31a47cd11efb6cf663a527177e432
https://git.kernel.org/stable/c/fb1cae6302d58414ddf029e3f642711bd30243f7

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 06:17

Updated : 2026-08-18 07:16

NVD link : CVE-2026-68457

Mitre link : CVE-2026-68457

CVE.ORG link : CVE-2026-68457

JSON object : View

Products Affected

No product.

CWE

No CWE.

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