CVE-2026-31478
9.8
CRITICAL
CVSS 3.1
EPSS 0.10%
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.
How to fix CVE-2026-31478
To remediate CVE-2026-31478, upgrade the affected package to a fixed version below.
- —upgrade to 6.1.170-1 or later
- —upgrade to 6.1.170-1~deb11u1 or later
Is CVE-2026-31478 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 6.1.170-1
- from 0, < 6.1.170-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |