CVE-2026-31478

In the Linux kernel, the following vulnerability has been resolved: ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len() After this commit (e2b76ab8b5c9 "ksmbd: add support for read compound"), response buffer management was changed to use dynamic iov array. In the new design, smb2_calc_max_out_buf_len() expects the second argument (hdr2_len) to be the offset of ->Buffer field in the response structure, not a hardcoded magic number. Fix the remaining call sites to use the correct offsetof() value.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0e55f63dd08f09651d39e1b709a91705a8a0ddcb	Patch
https://git.kernel.org/stable/c/4cb537ae4f37d7d0f617815ed4bed7173fb50861	Patch
https://git.kernel.org/stable/c/6aef1765d6807e0f027cd87f6ac973eb0879a46d	Patch
https://git.kernel.org/stable/c/70b4c414889492c522b6e4331562360f49be2361	Patch
https://git.kernel.org/stable/c/80824c7e527b70cf9039534e60aff592e8f209d1	Patch
https://git.kernel.org/stable/c/9a7166f0ef8cbb7bb48dd05e2471d995566003f5	Patch
https://git.kernel.org/stable/c/c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683	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:6.6:-::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc4::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc5::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc6::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc7::::::

History

No history.

Information

Published : 2026-04-22 14:16

Updated : 2026-06-17 10:33

NVD link : CVE-2026-31478

Mitre link : CVE-2026-31478

CVE.ORG link : CVE-2026-31478

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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