Vulnerability 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.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 5.15.145, < 5.15.203 |
References
- https://git.kernel.org/stable/c/0e55f63dd08f09651d39e1b709a91705a8a0ddcbPatch
- https://git.kernel.org/stable/c/4cb537ae4f37d7d0f617815ed4bed7173fb50861Patch
- https://git.kernel.org/stable/c/6aef1765d6807e0f027cd87f6ac973eb0879a46dPatch
- https://git.kernel.org/stable/c/70b4c414889492c522b6e4331562360f49be2361Patch
- https://git.kernel.org/stable/c/80824c7e527b70cf9039534e60aff592e8f209d1Patch
- https://git.kernel.org/stable/c/9a7166f0ef8cbb7bb48dd05e2471d995566003f5Patch
- https://git.kernel.org/stable/c/c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683Patch
FAQ
What is CVE-2026-31478?
CVE-2026-31478 is a vulnerability with a CVSS score of 9.8 (CRITICAL). 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 suppo...
How severe is CVE-2026-31478?
CVE-2026-31478 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-31478?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.