CVE-2026-64380

In the Linux kernel, the following vulnerability has been resolved: smb: client: harden POSIX SID length parsing posix_info_sid_size() reads sid[1] to obtain the subauthority count, but its existing boundary check still accepts buffers with only one remaining byte. Require two bytes before reading sid[1] so all client paths that reuse the helper reject truncated POSIX SIDs safely.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0de5b8e76847f5de26f364a82c6602c4881c30da	Patch
https://git.kernel.org/stable/c/171605aed68380c2fa75dff9b3a1ed427c50065b	Patch
https://git.kernel.org/stable/c/4213c1208978483021d7d125c131de3985d38f61	Patch
https://git.kernel.org/stable/c/427eb7eb46425fec845a43e861f3d6e2899cae59	Patch
https://git.kernel.org/stable/c/46a84715a015cb48e1b9c219dc88c03d8a541ea4	Patch
https://git.kernel.org/stable/c/7ad2bcf2441430bb2e918fb3ef9a90d775a6e422	Patch
https://git.kernel.org/stable/c/86c5d470f5d42e61123b2f4b4f0b91f4eee5b980	Patch
https://git.kernel.org/stable/c/96e889bc1e759c83f25093e8c2f3da31b4973f30	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::::::::
	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:7.2:rc1::::::

History

No history.

Information

Published : 2026-07-25 10:17

Updated : 2026-09-08 14:06

NVD link : CVE-2026-64380

Mitre link : CVE-2026-64380

CVE.ORG link : CVE-2026-64380

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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existing boundary check still accepts buffers with only one\nremaining byte. 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