ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len() (Linux Linux)

CVE-2026-31478
CRITICAL 9.8

At a glance

Source
NVD
EPSS
EPSS 0.50 % · percentile 43 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified

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.

Weaknesses (CWE)

  • CWE-131 — Incorrect Calculation of Buffer Size

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected f2283680a80571ca82d710bc6ecd8f8beac67d63 < 70b4c414889492c522b6e4331562360f49be2361 ; affected 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 < 9a7166f0ef8cbb7bb48dd05e2471d995566003f5 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < 6aef1765d6807e0f027cd87f6ac973eb0879a46d ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < 80824c7e527b70cf9039534e60aff592e8f209d1 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < 4cb537ae4f37d7d0f617815ed4bed7173fb50861
Linux · Linuxaffected 6.6 ; unaffected 0 < 6.6 ; unaffected 5.15.203 ≤ 5.15.* ; unaffected 6.1.168 ≤ 6.1.* ; unaffected 6.6.131 ≤ 6.6.* ; unaffected 6.12.80 ≤ 6.12.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD