ksmbd: fix OOB write in QUERY_INFO for compound requests (Linux Linux)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.51 % · percentile 43 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix OOB write in QUERY_INFO for compound requests When a compound request such as READ + QUERY_INFO(Security) is received, and the first command (READ) consumes most of the response buffer, ksmbd could write beyond the allocated buffer while building a security descriptor. The root cause was that smb2_get_info_sec() checked buffer space using ppntsd_size from xattr, while build_sec_desc() often synthesized a significantly larger descriptor from POSIX ACLs. This patch introduces smb_acl_sec_desc_scratch_len() to accurately compute the final descriptor size beforehand, performs proper buffer checking with smb2_calc_max_out_buf_len(), and uses exact-sized allocation + iov pinning.
Weaknesses (CWE)
- CWE-787 — Out-of-bounds Write
References
- https://git.kernel.org/stable/c/533f84264e28c54a79257ea87d2f94a0fcc9a611
- https://git.kernel.org/stable/c/850452af77f55d185f9445e1f7a1db53c5e4aad4
- https://git.kernel.org/stable/c/d48c64fb80ad78b3dd29fb7d79b6ec7bd72bfc09
- https://git.kernel.org/stable/c/075ea208c648cc2bcd616295b711d3637c61de45
- https://git.kernel.org/stable/c/515c2daab46021221bdf406bef19bc90a44ec617
- https://git.kernel.org/stable/c/fda9522ed6afaec45cabc198d8492270c394c7bc
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | Linux |
| CVSS 3.1 | HIGH 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-24640
- GCVE · GCVE-0-2026-31432
CERT-FR advisories
- CERTFR-2026-AVI-1066 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0954 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0926 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0548 — Multiples vulnérabilités dans le noyau Linux de Debian · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.15.145 < 5.16cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.1.71 < 6.2cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.6 < 6.12.81cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.22cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 6.19.12cpe: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:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 < 533f84264e28c54a79257ea87d2f94a0fcc9a611 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < 850452af77f55d185f9445e1f7a1db53c5e4aad4 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < d48c64fb80ad78b3dd29fb7d79b6ec7bd72bfc09 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < 075ea208c648cc2bcd616295b711d3637c61de45 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < 515c2daab46021221bdf406bef19bc90a44ec617 ; affected e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d < fda9522ed6afaec45cabc198d8492270c394c7bc |
| Linux · Linux | affected 6.6 ; unaffected 0 < 6.6 ; unaffected 6.1.191 ≤ 6.1.* ; unaffected 6.6.143 ≤ 6.6.* ; unaffected 6.12.81 ≤ 6.12.* ; unaffected 6.18.22 ≤ 6.18.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |