ksmbd: fix signededness bug in smb_direct_prepare_negotiation() (Linux Linux)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.89 % · percentile 59 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix signededness bug in smb_direct_prepare_negotiation() smb_direct_prepare_negotiation() casts an unsigned __u32 value from sp->max_recv_size and req->preferred_send_size to a signed int before computing min_t(int, ...). A maliciously provided preferred_send_size of 0x80000000 will return as smaller than max_recv_size, and then be used to set the maximum allowed alowed receive size for the next message. By sending a second message with a large value (>1420 bytes) the attacker can then achieve a heap buffer overflow. This fix replaces min_t(int, ...) with min_t(u32)
Weaknesses (CWE)
- CWE-674 — Uncontrolled Recursion
References
- https://git.kernel.org/stable/c/1c268fd2f59dc9ccb2c2a7d1f439b232dbe1c06c
- https://git.kernel.org/stable/c/56eab82fa6fb5ca024b0514e249d40d9b23ee5a7
- https://git.kernel.org/stable/c/a110dbe928561d440e9e117d17331139a0bedace
- https://git.kernel.org/stable/c/ceae058eb707ddd0d68f0872f9d9f23b7c30c37b
- https://git.kernel.org/stable/c/55abc475d096da4a5356b6efb0cfdc6156bc1550
- https://git.kernel.org/stable/c/6b4f875aac344cdd52a1f34cc70ed2f874a65757
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | Linux |
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-27748
- GCVE · GCVE-0-2026-43185
CERT-FR advisories
- CERTFR-2026-AVI-1093 — 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-0898 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.15 < 6.18.16cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 6.19.6cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected 0626e6641f6b467447c81dd7678a69c66f7746cf < 1c268fd2f59dc9ccb2c2a7d1f439b232dbe1c06c ; affected 0626e6641f6b467447c81dd7678a69c66f7746cf < 56eab82fa6fb5ca024b0514e249d40d9b23ee5a7 ; affected 0626e6641f6b467447c81dd7678a69c66f7746cf < a110dbe928561d440e9e117d17331139a0bedace ; affected 0626e6641f6b467447c81dd7678a69c66f7746cf < ceae058eb707ddd0d68f0872f9d9f23b7c30c37b ; affected 0626e6641f6b467447c81dd7678a69c66f7746cf < 55abc475d096da4a5356b6efb0cfdc6156bc1550 ; affected 0626e6641f6b467447c81dd7678a69c66f7746cf < 6b4f875aac344cdd52a1f34cc70ed2f874a65757 |
| Linux · Linux | affected 5.15 ; unaffected 0 < 5.15 ; unaffected 6.1.191 ≤ 6.1.* ; unaffected 6.6.160 ≤ 6.6.* ; unaffected 6.12.114 ≤ 6.12.* ; unaffected 6.18.16 ≤ 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 |