Answer in brief
CVE-2026-31478 records a Critical severity (CVSS 9.8) vulnerability in ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=f2283680a80571ca82d710bc6ecd8f8beac67d63 <70b4c414889492c522b6e4331562360f49be2361 || >=9f297df20d93411c0b4ddad7f88ba04a7cd36e77 <9a7166f0ef8cbb7bb48dd05e2471d995566003f5 || >=e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d <c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683 || >=e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d <6aef1765d6807e0f027cd87f6ac973eb0879a46d || >=e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d <80824c7e527b70cf9039534e60aff592e8f209d1 || >=e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d <4cb537ae4f37d7d0f617815ed4bed7173fb50861 || >=e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d <0e55f63dd08f09651d39e1b709a91705a8a0ddcb || >=5.15.145 <5.15.203 || >=6.1.71 <6.1.168 | 70b4c414889492c522b6e4331562360f49be2361, 9a7166f0ef8cbb7bb48dd05e2471d995566003f5, c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683, 6aef1765d6807e0f027cd87f6ac973eb0879a46d, 80824c7e527b70cf9039534e60aff592e8f209d1, 4cb537ae4f37d7d0f617815ed4bed7173fb50861, 0e55f63dd08f09651d39e1b709a91705a8a0ddcb, 5.15.203, 6.1.168 |
| Linux/Linuxgeneric | 6.6 | Not reported |
Published upstream
Apr 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 16, 2026
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.
Quoted source text, attributed separately from HOL analysis.