CVE-2026-31478

high

Description

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.

References

https://git.kernel.org/stable/c/c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683

https://git.kernel.org/stable/c/9a7166f0ef8cbb7bb48dd05e2471d995566003f5

https://git.kernel.org/stable/c/80824c7e527b70cf9039534e60aff592e8f209d1

https://git.kernel.org/stable/c/70b4c414889492c522b6e4331562360f49be2361

https://git.kernel.org/stable/c/6aef1765d6807e0f027cd87f6ac973eb0879a46d

https://git.kernel.org/stable/c/4cb537ae4f37d7d0f617815ed4bed7173fb50861

https://git.kernel.org/stable/c/0e55f63dd08f09651d39e1b709a91705a8a0ddcb

Details

Source: Mitre, NVD

Published: 2026-04-22

Updated: 2026-04-23

Risk Information

CVSS v2

Base Score: 9.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:C/A:C

Severity: High

CVSS v3

Base Score: 7.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.0003