CVE-2026-45859

Source
https://cve.org/CVERecord?id=CVE-2026-45859
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-45859.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-45859
Downstream
AZL (1)
BELL (1)
DEBIAN (1)
OESA (2)
openSUSE (1)
RHSA (1)
RLSA (1)
ROOT (3)
SUSE (5)
UBUNTU (1)
Related
Published
2026-05-27T12:15:39Z
Modified
2026-10-22T02:48:53Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation
Details

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

netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation

Ulrich reports a regression with nfqueue:

If an application did not set the 'F_GSO' capability flag and a gso packet with an unconfirmed nf_conn entry is received all packets are now dropped instead of queued, because the check happens after skb_gso_segment(). In that case, we did have exclusive ownership of the skb and its associated conntrack entry. The elevated use count is due to skb_clone happening via skb_gso_segment().

Move the check so that its peformed vs. the aggregated packet.

Then, annotate the individual segments except the first one so we can do a 2nd check at reinject time.

For the normal case, where userspace does in-order reinjects, this avoids packet drops: first reinjected segment continues traversal and confirms entry, remaining segments observe the confirmed entry.

While at it, simplify nf_ct_drop_unconfirmed(): We only care about unconfirmed entries with a refcnt > 1, there is no need to special-case dying entries.

This only happens with UDP. With TCP, the only unconfirmed packet will be the TCP SYN, those aren't aggregated by GRO.

Next patch adds a udpgro test case to cover this scenario.

Database specific
{
    "cna_assigner":  "Linux",
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45859.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
74e6eb7fd27ef1ccc68041dbc66e6d80d2e4a1a0
Fixed
aead84bdacd77e08357fd718e5dcaffaf387f3c3
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb
Fixed
79b713ef4261a8ead96af4703f89d0b5f25532e2
Fixed
23901aa6b8a2f294c4b774436b4691f3ff863a8f
Fixed
b740e7ddd7ca0dbfeafca3f5e52717206cf28524
Fixed
207b3ebacb6113acaaec0d171d5307032c690004
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.6.48
Fixed
6.6.160
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
5.15.166
Fixed
5.16
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.1.107
Fixed
6.2
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.10.7
Fixed
6.11
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6c4a0ba674f410ab99a30a16f32dac0ebfed5cd3
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6dcc8ba8a6074bb79040f502dc66ad23a58a1c86
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
025b3326c5c409b372d0103ad30f174e55adbd1b

Affected versions

v5.*
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.*
v6.1.107
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
v6.10.10
v6.10.11
v6.10.12
v6.10.13
v6.10.14
v6.10.7
v6.10.8
v6.10.9
v6.6.100
v6.6.101
v6.6.102
v6.6.103
v6.6.104
v6.6.105
v6.6.106
v6.6.107
v6.6.108
v6.6.109
v6.6.110
v6.6.111
v6.6.112
v6.6.113
v6.6.114
v6.6.115
v6.6.116
v6.6.117
v6.6.118
v6.6.119
v6.6.120
v6.6.121
v6.6.122
v6.6.123
v6.6.124
v6.6.125
v6.6.126
v6.6.127
v6.6.128
v6.6.129
v6.6.130
v6.6.131
v6.6.132
v6.6.133
v6.6.134
v6.6.135
v6.6.136
v6.6.137
v6.6.138
v6.6.139
v6.6.140
v6.6.141
v6.6.142
v6.6.143
v6.6.144
v6.6.145
v6.6.146
v6.6.147
v6.6.148
v6.6.149
v6.6.150
v6.6.151
v6.6.152
v6.6.153
v6.6.154
v6.6.155
v6.6.156
v6.6.157
v6.6.158
v6.6.159
v6.6.48
v6.6.49
v6.6.50
v6.6.51
v6.6.52
v6.6.53
v6.6.54
v6.6.55
v6.6.56
v6.6.57
v6.6.58
v6.6.59
v6.6.60
v6.6.61
v6.6.62
v6.6.63
v6.6.64
v6.6.65
v6.6.66
v6.6.67
v6.6.68
v6.6.69
v6.6.70
v6.6.71
v6.6.72
v6.6.73
v6.6.74
v6.6.75
v6.6.76
v6.6.77
v6.6.78
v6.6.79
v6.6.80
v6.6.81
v6.6.82
v6.6.83
v6.6.84
v6.6.85
v6.6.86
v6.6.87
v6.6.88
v6.6.89
v6.6.90
v6.6.91
v6.6.92
v6.6.93
v6.6.94
v6.6.95
v6.6.96
v6.6.97
v6.6.98
v6.6.99

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-45859.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.6.160
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.12.75
Type
ECOSYSTEM
Events
Introduced
6.11.0
Fixed
6.18.14
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
6.19.4

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-45859.json"