CVE-2026-31478

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Source
https://cve.org/CVERecord?id=CVE-2026-31478
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31478.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-31478
Downstream
Published
2026-04-22T13:54:06.157Z
Modified
2026-05-18T05:59:49.831427484Z
Severity
  • 9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()
Details

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: replace hardcoded hdr2len with offsetof() in smb2calcmaxoutbuflen()

After this commit (e2b76ab8b5c9 "ksmbd: add support for read compound"), response buffer management was changed to use dynamic iov array. In the new design, smb2calcmaxoutbuflen() expects the second argument (hdr2len) 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.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31478.json",
    "cna_assigner": "Linux"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
f2283680a80571ca82d710bc6ecd8f8beac67d63
Fixed
70b4c414889492c522b6e4331562360f49be2361
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
9f297df20d93411c0b4ddad7f88ba04a7cd36e77
Fixed
9a7166f0ef8cbb7bb48dd05e2471d995566003f5
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d
Fixed
c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683
Fixed
6aef1765d6807e0f027cd87f6ac973eb0879a46d
Fixed
80824c7e527b70cf9039534e60aff592e8f209d1
Fixed
4cb537ae4f37d7d0f617815ed4bed7173fb50861
Fixed
0e55f63dd08f09651d39e1b709a91705a8a0ddcb

Affected versions

v5.*
v5.15.145
v5.15.146
v5.15.147
v5.15.148
v5.15.149
v5.15.150
v5.15.151
v5.15.152
v5.15.153
v5.15.154
v5.15.155
v5.15.156
v5.15.157
v5.15.158
v5.15.159
v5.15.160
v5.15.161
v5.15.162
v5.15.163
v5.15.164
v5.15.165
v5.15.166
v5.15.167
v5.15.168
v5.15.169
v5.15.170
v5.15.171
v5.15.172
v5.15.173
v5.15.174
v5.15.175
v5.15.176
v5.15.177
v5.15.178
v5.15.179
v5.15.180
v5.15.181
v5.15.182
v5.15.183
v5.15.184
v5.15.185
v5.15.186
v5.15.187
v5.15.188
v5.15.189
v5.15.190
v5.15.191
v5.15.192
v5.15.193
v5.15.194
v5.15.195
v5.15.196
v5.15.197
v5.15.198
v5.15.199
v5.15.200
v5.15.201
v5.15.202
v6.*
v6.1.100
v6.1.101
v6.1.102
v6.1.103
v6.1.104
v6.1.105
v6.1.106
v6.1.107
v6.1.108
v6.1.109
v6.1.110
v6.1.111
v6.1.112
v6.1.113
v6.1.114
v6.1.115
v6.1.116
v6.1.117
v6.1.118
v6.1.119
v6.1.120
v6.1.121
v6.1.122
v6.1.123
v6.1.124
v6.1.125
v6.1.126
v6.1.127
v6.1.128
v6.1.129
v6.1.130
v6.1.131
v6.1.132
v6.1.133
v6.1.134
v6.1.135
v6.1.136
v6.1.137
v6.1.138
v6.1.139
v6.1.140
v6.1.141
v6.1.142
v6.1.143
v6.1.144
v6.1.145
v6.1.146
v6.1.147
v6.1.148
v6.1.149
v6.1.150
v6.1.151
v6.1.152
v6.1.153
v6.1.154
v6.1.155
v6.1.156
v6.1.157
v6.1.158
v6.1.159
v6.1.160
v6.1.161
v6.1.162
v6.1.163
v6.1.164
v6.1.165
v6.1.166
v6.1.167
v6.1.71
v6.1.72
v6.1.73
v6.1.74
v6.1.75
v6.1.76
v6.1.77
v6.1.78
v6.1.79
v6.1.80
v6.1.81
v6.1.82
v6.1.83
v6.1.84
v6.1.85
v6.1.86
v6.1.87
v6.1.88
v6.1.89
v6.1.90
v6.1.91
v6.1.92
v6.1.93
v6.1.94
v6.1.95
v6.1.96
v6.1.97
v6.1.98
v6.1.99

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31478.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.15.203
Type
ECOSYSTEM
Events
Introduced
5.16.0
Fixed
6.1.168
Type
ECOSYSTEM
Events
Introduced
6.2.0
Fixed
6.6.131
Type
ECOSYSTEM
Events
Introduced
6.6.0
Fixed
6.12.80
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.18.21
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
6.19.11

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31478.json"