CVE-2026-31478 (GCVE-0-2026-31478)
Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-04-27 14:03
VLAI?
Title
ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()
Summary
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.
Severity ?
9.8 (Critical)
Assigner
References
Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux |
Affected:
f2283680a80571ca82d710bc6ecd8f8beac67d63 , < 70b4c414889492c522b6e4331562360f49be2361
(git)
Affected: 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 , < 9a7166f0ef8cbb7bb48dd05e2471d995566003f5 (git) Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683 (git) Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < 6aef1765d6807e0f027cd87f6ac973eb0879a46d (git) Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < 80824c7e527b70cf9039534e60aff592e8f209d1 (git) Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < 4cb537ae4f37d7d0f617815ed4bed7173fb50861 (git) Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < 0e55f63dd08f09651d39e1b709a91705a8a0ddcb (git) |
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|
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}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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