CVE-2026-31478
Last modified
CVE-2026-31478 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 0.50% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 5.15.145, < 5.15.203 | — |
| Linux | Linux Kernel | >= 6.1.71, < 6.1.168 | — |
| Linux | Linux Kernel | >= 6.6.1, < 6.6.131 | — |
| Linux | Linux Kernel | >= 6.7, < 6.12.80 | — |
| Linux | Linux Kernel | >= 6.13, < 6.18.21 | — |
| Linux | Linux Kernel | >= 6.19, < 6.19.11 | — |
| Linux | Linux Kernel | 6.6 | — |
| Linux | Linux Kernel | 7.0 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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