CVE-2026-99083

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Source
https://cve.org/CVERecord?id=CVE-2026-99083
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99083.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-99083
Downstream
Published
2026-10-23T12:45:01Z
Modified
2026-11-01T02:30:26Z
Severity
  • 8.8 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
ksmbd: fix heap out-of-bounds write in krb5_authenticate()
Details

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

ksmbd: fix heap out-of-bounds write in krb5_authenticate()

In krb5_authenticate(), out_len is calculated to determine available headroom in response_buf for the incoming Kerberos AP-REP token. However, when SMB2_SESSION_SETUP is processed as a non-first element of a compounded SMB2 request, the calculation omits work->next_smb2_rsp_hdr_off.

This causes out_len to overstate remaining buffer headroom by the cumulative size of prior responses in the compound chain. Consequently, the length check in ksmbd_krb5_authenticate() (*out_len <= resp->spnego_blob_len) passes erroneously, allowing memcpy() to write the AP-REP blob past the end of response_buf into adjacent kernel heap memory.

Fix this by subtracting work->next_smb2_rsp_hdr_off when computing out_len, ensuring it accurately reflects physical remaining buffer space.

Database specific 
{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99083.json"
}
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
676392184785ace61e939831e7ca44a03d438c3b
Fixed
a07dfb33112a42437f9d2d0bfd35c68575257381
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
ef572ffa8eb44111eed2925fbb2adca78bdcbf61
Fixed
1f73a6d40f4d1bae4f3491c0ec1ea8ee6ce035ff
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
98422bdd4cb3ca4d08844046f6507d7ec2c2b8d8
Fixed
59c6dcc5dd9dafe764ca0d40525933b2be69b059
Fixed
80af1bde97d5a85ad6f2c40ca894ccc8fa75a27a
Fixed
517404e157395d0f8da125ca956c566895dfcd06
Fixed
4722d06b2907585074252061b1024a696c1cfc23
Fixed
23a0be6a84a38ac169eeab49017934e8e27c65f0
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
5.15.145
Fixed
5.15.224
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.1.40
Fixed
6.1.191
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.4.5
Fixed
6.5
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
2ba03cecb12ac7ac9e0170e251543c56832d9959

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
v5.15.203
v5.15.204
v5.15.205
v5.15.206
v5.15.207
v5.15.208
v5.15.209
v5.15.210
v5.15.211
v5.15.212
v5.15.213
v5.15.214
v5.15.215
v5.15.216
v5.15.217
v5.15.218
v5.15.219
v5.15.220
v5.15.221
v5.15.222
v5.15.223
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
v6.1.168
v6.1.169
v6.1.170
v6.1.171
v6.1.172
v6.1.173
v6.1.174
v6.1.175
v6.1.176
v6.1.177
v6.1.178
v6.1.179
v6.1.180
v6.1.181
v6.1.182
v6.1.183
v6.1.184
v6.1.185
v6.1.186
v6.1.187
v6.1.188
v6.1.189
v6.1.190
v6.1.40
v6.1.41
v6.1.42
v6.1.43
v6.1.44
v6.1.45
v6.1.46
v6.1.47
v6.1.48
v6.1.49
v6.1.50
v6.1.51
v6.1.52
v6.1.53
v6.1.54
v6.1.55
v6.1.56
v6.1.57
v6.1.58
v6.1.59
v6.1.60
v6.1.61
v6.1.62
v6.1.63
v6.1.64
v6.1.65
v6.1.66
v6.1.67
v6.1.68
v6.1.69
v6.1.70
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
v6.4.10
v6.4.11
v6.4.12
v6.4.13
v6.4.14
v6.4.15
v6.4.16
v6.4.5
v6.4.6
v6.4.7
v6.4.8
v6.4.9

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99083.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
5.15.224
Type
ECOSYSTEM
Events
Introduced
5.16.0
Fixed
6.1.191
Type
ECOSYSTEM
Events
Introduced
6.2.0
Fixed
6.6.160
Type
ECOSYSTEM
Events
Introduced
6.5.0
Fixed
6.12.114
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.18.58
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
7.2.12

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-99083.json"