|
Vulnerabilities
< Back

CVE-2026-31478

Updated on 22 Apr 2026

Severity

7.5 High severity

Details

CVSS score
7.5
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Links
NISTCIRCLRHELUbuntu

Overview

About vulnerability

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.

Details

Affected product:
Ubuntu 20.04 ELS
Affected packages:
linux @ 5.4.0 (+1 more)

Fixes

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Debian 12 Released
25 kernels
  • 6.1.76-1
  • 6.1.85-1
  • 6.1.90-1
  • 6.1.94-1
  • 6.1.99-1
  • 6.1.106-3
  • 6.1.112-1
  • 6.1.115-1
  • 6.1.119-1
  • 6.1.123-1
  • 6.1.128-1
  • 6.1.124-1
  • 6.1.129-1
  • 6.1.133-1
  • 6.1.135-1
  • 6.1.137-1
  • 6.1.140-1
  • 6.1.139-1
  • 6.1.147-1
  • 6.1.148-1
  • 6.1.153-1
  • 6.1.158-1
  • 6.1.159-1
  • 6.1.162-1
  • 6.1.164-1
Debian 13 Planned —
Proxmox VE 7 5.15 Released
4 kernels
  • 5.15.149-1-pve-5.15.149-1
  • 5.15.152-1-pve-5.15.152-1
  • 5.15.158-1-pve_5.15.158-1
  • 5.15.158-2-pve_5.15.158-2
Ubuntu 20.04 HWE AWS Released
22 kernels
  • 5.15.0-1057.63~20.04.1
  • 5.15.0-1058.64~20.04.1
  • 5.15.0-1061.67~20.04.1
  • 5.15.0-1062.68~20.04.1
  • 5.15.0-1063.69~20.04.1
  • 5.15.0-1064.70~20.04.1
  • 5.15.0-1065.71~20.04.1
  • 5.15.0-1066.72~20.04.1
  • 5.15.0-1067.73~20.04.1
  • 5.15.0-1068.74~20.04.1
  • 5.15.0-1069.75~20.04.1
  • 5.15.0-1070.76~20.04.1
  • 5.15.0-1071.77~20.04.1
  • 5.15.0-1072.78~20.04.1
  • 5.15.0-1073.79~20.04.1
  • 5.15.0-1075.82~20.04.1
  • 5.15.0-1077.84~20.04.1
  • 5.15.0-1080.87~20.04.1
  • 5.15.0-1081.88~20.04.1
  • 5.15.0-1082.89~20.04.1
  • 5.15.0-1083.90~20.04.1
  • 5.15.0-1084.91~20.04.1
Ubuntu 20.04 HWE Azure Released
21 kernels
  • 5.15.0-1060.69~20.04.1
  • 5.15.0-1061.70~20.04.1
  • 5.15.0-1063.72~20.04.1
  • 5.15.0-1064.73~20.04.1
  • 5.15.0-1067.76~20.04.1
  • 5.15.0-1068.77~20.04.1
  • 5.15.0-1065.74~20.04.1
  • 5.15.0-1070.79~20.04.1
  • 5.15.0-1071.80~20.04.1
  • 5.15.0-1072.81~20.04.1
  • 5.15.0-1073.82~20.04.1
  • 5.15.0-1074.83~20.04.1
  • 5.15.0-1075.84~20.04.1
  • 5.15.0-1078.87~20.04.1
  • 5.15.0-1079.88~20.04.1
  • 5.15.0-1081.90~20.04.1
  • 5.15.0-1082.91~20.04.1
  • 5.15.0-1086.95~20.04.1
  • 5.15.0-1087.96~20.04.1
  • 5.15.0-1088.97~20.04.1
  • 5.15.0-1089.98~20.04.1
Ubuntu 22.04 Released
48 kernels
  • 5.15.0-102.112
  • 5.15.0-105.115
  • 5.15.0-106.116
  • 5.15.0-107.117
  • 5.15.0-112.122
  • 5.15.0-113.123
  • 5.15.0-116.126
  • 5.15.0-117.127
  • 5.15.0-118.128
  • 5.15.0-119.129
  • 5.15.0-121.131
  • 5.15.0-122.132
  • 5.15.0-124.134
  • 5.15.0-125.135
  • 5.15.0-127.137
  • 5.15.0-130.140
  • 5.15.0-126.136
  • 5.15.0-131.141
  • 5.15.0-128.138
  • 5.15.0-133.144
  • 5.15.0-134.145
  • 5.15.0-135.146
  • 5.15.0-136.147
  • 5.15.0-138.148
  • 5.15.0-139.149
  • 5.15.0-140.150
  • 5.15.0-141.151
  • 5.15.0-142.152
  • 5.15.0-143.153
  • 5.15.0-144.157
  • 5.15.0-151.161
  • 5.15.0-152.162
  • 5.15.0-153.163
  • 5.15.0-156.166
  • 5.15.0-157.167
  • 5.15.0-160.170
  • 5.15.0-161.171
  • 5.15.0-163.173
  • 5.15.0-164.174
  • 5.15.0-168.178
  • 5.15.0-170.180
  • 5.15.0-171.181
  • 5.15.0-173.183
  • 5.15.0-174.184
  • 5.15.0-176.186
  • 5.15.0-177.187
  • 5.15.0-179.189
  • 5.15.0-181.191
Ubuntu 22.04 AWS Released
45 kernels
  • 5.15.0-1057.63
  • 5.15.0-1060.66
  • 5.15.0-1061.67
  • 5.15.0-1062.68
  • 5.15.0-1063.69
  • 5.15.0-1064.70
  • 5.15.0-1065.71
  • 5.15.0-1066.72
  • 5.15.0-1067.73
  • 5.15.0-1068.74
  • 5.15.0-1069.75
  • 5.15.0-1070.76
  • 5.15.0-1071.77
  • 5.15.0-1072.78
  • 5.15.0-1073.79
  • 5.15.0-1076.83
  • 5.15.0-1078.85
  • 5.15.0-1079.86
  • 5.15.0-1080.87
  • 5.15.0-1081.88
  • 5.15.0-1082.89
  • 5.15.0-1083.90
  • 5.15.0-1084.91
  • 5.15.0-1085.92
  • 5.15.0-1086.93
  • 5.15.0-1087.94
  • 5.15.0-1088.95
  • 5.15.0-1089.96
  • 5.15.0-1090.97
  • 5.15.0-1091.98
  • 5.15.0-1092.99
  • 5.15.0-1093.100
  • 5.15.0-1095.102
  • 5.15.0-1096.103
  • 5.15.0-1097.104
  • 5.15.0-1098.105
  • 5.15.0-1099.106
  • 5.15.0-1100.107
  • 5.15.0-1101.108
  • 5.15.0-1103.110
  • 5.15.0-1104.111
  • 5.15.0-1105.112
  • 5.15.0-1106.113
  • 5.15.0-1108.115
  • 5.15.0-1109.116
Ubuntu 22.04 Azure Released
38 kernels
  • 5.15.0-1060.69
  • 5.15.0-1061.70
  • 5.15.0-1063.72
  • 5.15.0-1064.73
  • 5.15.0-1066.75
  • 5.15.0-1067.76
  • 5.15.0-1068.77
  • 5.15.0-1070.79
  • 5.15.0-1071.80
  • 5.15.0-1072.81
  • 5.15.0-1073.82
  • 5.15.0-1074.83
  • 5.15.0-1075.84
  • 5.15.0-1078.87
  • 5.15.0-1079.88
  • 5.15.0-1081.90
  • 5.15.0-1082.91
  • 5.15.0-1084.93
  • 5.15.0-1086.95
  • 5.15.0-1087.96
  • 5.15.0-1088.97
  • 5.15.0-1089.98
  • 5.15.0-1090.99
  • 5.15.0-1091.100
  • 5.15.0-1092.101
  • 5.15.0-1094.103
  • 5.15.0-1095.104
  • 5.15.0-1096.105
  • 5.15.0-1097.106
  • 5.15.0-1098.107
  • 5.15.0-1101.110
  • 5.15.0-1102.111
  • 5.15.0-1099.108
  • 5.15.0-1103.112
  • 5.15.0-1109.118
  • 5.15.0-1110.119
  • 5.15.0-1111.120
  • 5.15.0-1114.123
Ubuntu 24.04 Released
45 kernels
  • 6.8.0-35.35
  • 6.8.0-38.38
  • 6.8.0-36.36
  • 6.8.0-39.39
  • 6.8.0-40.40
  • 6.8.0-41.41
  • 6.8.0-44.44
  • 6.8.0-45.45
  • 6.8.0-31.31
  • 6.8.0-47.47
  • 6.8.0-48.48
  • 6.8.0-49.49
  • 6.8.0-50.51
  • 6.8.0-51.52
  • 6.8.0-52.53
  • 6.8.0-54.56
  • 6.8.0-55.57
  • 6.8.0-53.55
  • 6.8.0-56.58
  • 6.8.0-57.59
  • 6.8.0-58.60
  • 6.8.0-59.61
  • 6.8.0-60.63
  • 6.8.0-62.65
  • 6.8.0-63.66
  • 6.8.0-64.67
  • 6.8.0-71.71
  • 6.8.0-78.78
  • 6.8.0-79.79
  • 6.8.0-84.84
  • 6.8.0-85.85
  • 6.8.0-83.83
  • 6.8.0-86.87
  • 6.8.0-87.88
  • 6.8.0-88.89
  • 6.8.0-90.91
  • 6.8.0-94.96
  • 6.8.0-100.100
  • 6.8.0-101.101
  • 6.8.0-106.106
  • 6.8.0-107.107
  • 6.8.0-110.110
  • 6.8.0-111.111
  • 6.8.0-117.117
  • 6.8.0-124.124
Ubuntu 24.04 AWS Planned —