CVE-2026-72493

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Source
https://cve.org/CVERecord?id=CVE-2026-72493
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72493.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-72493
Downstream
Published
2026-08-15T05:57:27.642Z
Modified
2026-08-16T03:48:34.424027112Z
Summary
net: serialize netif_running() check in enqueue_to_backlog()
Details

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

net: serialize netifrunning() check in enqueueto_backlog()

Syzbot reported a KASAN slab-use-after-free in fibruleslookup().

The root cause is a race condition where packets can escape the backlog flushing during device unregistration (e.g., during netns exit).

Commit e9e4dd3267d0 ("net: do not process device backlog during unregistration") introduced a lockless netifrunning() check in enqueueto_backlog() to prevent queuing packets to an unregistering device.

However, this creates a TOCTOU race window.

A lockless transmitter (like vethxmit) can pass the check before devclose() clears IFFUP. If the transmitter is then delayed, flushall_backlogs() can run and finish before the transmitter grabs the backlog lock and queues the packet. The packet then escapes the flush and triggers UAF later when processed.

Fix this by moving the netifrunning() check inside the backlog lock. This serializes the check with the flush work (which also grabs the lock). We then either queue the packet before the flush runs (so it gets flushed), or check netifrunning() after the flush/close completes (so it gets dropped).

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72493.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
e9e4dd3267d0c5234c5c0f47440456b10875dec9
Fixed
2fface6e0bbd6314d1d9d071abf2c4d67548511c
Fixed
46762cefe7f4e5bffc1eb467810a7bbb02e461d7
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Last affected
78b6803a1961369d0b8350ff1f99b7375bbd7a8f
Last affected
b5d73d9cdd6be22795499890ea928a6f57ef829c
Last affected
f6533fed1bfa842e391ee50f9a9c5e963c71e579
Last affected
2095ab2456da766174cda8bc105d7a7b1bc70e16
Last affected
f1fdb184aefa8447560e3ea0e605171592ffee41
Last affected
f75c8a3015422128ca150e81c730bc2a471b5f4a
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.2.71
Fixed
3.3
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.4.111
Fixed
3.5
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.12.48
Fixed
3.13
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.14.54
Fixed
3.15
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.18.22
Fixed
3.19
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
4.1.9
Fixed
4.2

Affected versions

v2.*
v2.6.12-rc2
v2.6.12-rc3
v2.6.12-rc4
v2.6.13
v2.6.13-rc1
v2.6.13-rc2
v2.6.13-rc3
v2.6.13-rc4
v2.6.13-rc5
v2.6.13-rc6
v2.6.13-rc7
v2.6.14-rc1
v2.6.14-rc2
v2.6.14-rc3
v2.6.15-rc1
v2.6.15-rc2
v2.6.15-rc4
v2.6.15-rc5
v2.6.15-rc7
v2.6.16
v2.6.16-rc1
v2.6.16-rc2
v2.6.16-rc3
v2.6.16-rc4
v2.6.16-rc5
v2.6.16-rc6
v2.6.17
v2.6.17-rc1
v2.6.17-rc2
v2.6.17-rc3
v2.6.17-rc4
v2.6.17-rc5
v2.6.17-rc6
v2.6.18
v2.6.18-rc1
v2.6.18-rc2
v2.6.18-rc3
v2.6.18-rc5
v2.6.18-rc6
v2.6.19-rc1
v2.6.19-rc2
v2.6.20-rc1
v2.6.20-rc2
v2.6.20-rc3
v2.6.20-rc4
v2.6.20-rc5
v2.6.20-rc6
v2.6.20-rc7
v2.6.21
v2.6.21-rc1
v2.6.21-rc2
v2.6.21-rc3
v2.6.21-rc4
v2.6.21-rc5
v2.6.21-rc6
v2.6.21-rc7
v2.6.22
v2.6.22-rc1
v2.6.22-rc2
v2.6.22-rc3
v2.6.22-rc4
v2.6.22-rc5
v2.6.22-rc6
v2.6.22-rc7
v2.6.23
v2.6.23-rc1
v2.6.23-rc2
v2.6.23-rc3
v2.6.23-rc4
v2.6.23-rc5
v2.6.23-rc6
v2.6.23-rc7
v2.6.23-rc8
v2.6.23-rc9
v2.6.24
v2.6.24-rc1
v2.6.24-rc2
v2.6.24-rc3
v2.6.24-rc4
v2.6.24-rc5
v2.6.24-rc6
v2.6.24-rc7
v2.6.24-rc8
v2.6.25
v2.6.25-rc1
v2.6.25-rc2
v2.6.25-rc3
v2.6.25-rc4
v2.6.25-rc5
v2.6.25-rc6
v2.6.25-rc7
v2.6.25-rc8
v2.6.25-rc9
v2.6.26
v2.6.26-rc1
v2.6.26-rc2
v2.6.26-rc3
v2.6.26-rc4
v2.6.26-rc5
v2.6.26-rc6
v2.6.26-rc7
v2.6.26-rc8
v2.6.26-rc9
v2.6.27
v2.6.27-rc1
v2.6.27-rc2
v2.6.27-rc3
v2.6.27-rc4
v2.6.27-rc5
v2.6.27-rc6
v2.6.27-rc7
v2.6.27-rc8
v2.6.27-rc9
v2.6.28
v2.6.28-rc1
v2.6.28-rc2
v2.6.28-rc3
v2.6.28-rc4
v2.6.28-rc5
v2.6.28-rc6
v2.6.28-rc7
v2.6.28-rc8
v2.6.28-rc9
v2.6.29
v2.6.29-rc1
v2.6.29-rc2
v2.6.29-rc3
v2.6.29-rc4
v2.6.29-rc5
v2.6.29-rc6
v2.6.29-rc7
v2.6.29-rc8
v2.6.30
v2.6.30-rc1
v2.6.30-rc2
v2.6.30-rc3
v2.6.30-rc4
v2.6.30-rc5
v2.6.30-rc6
v2.6.30-rc7
v2.6.30-rc8
v2.6.31
v2.6.31-rc1
v2.6.31-rc2
v2.6.31-rc3
v2.6.31-rc4
v2.6.31-rc5
v2.6.31-rc6
v2.6.31-rc7
v2.6.31-rc8
v2.6.31-rc9
v2.6.32
v2.6.32-rc1
v2.6.32-rc2
v2.6.32-rc3
v2.6.32-rc4
v2.6.32-rc5
v2.6.32-rc6
v2.6.32-rc7
v2.6.32-rc8
v2.6.33
v2.6.33-rc1
v2.6.33-rc2
v2.6.33-rc3
v2.6.33-rc4
v2.6.33-rc5
v2.6.33-rc6
v2.6.33-rc7
v2.6.33-rc8
v2.6.34
v2.6.34-rc1
v2.6.34-rc2
v2.6.34-rc3
v2.6.34-rc4
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v2.6.35
v2.6.35-rc1
v2.6.35-rc2
v2.6.35-rc3
v2.6.35-rc4
v2.6.35-rc5
v2.6.35-rc6
v2.6.36
v2.6.36-rc1
v2.6.36-rc2
v2.6.36-rc3
v2.6.36-rc4
v2.6.36-rc5
v2.6.36-rc6
v2.6.36-rc7
v2.6.36-rc8
v2.6.37
v2.6.37-rc1
v2.6.37-rc2
v2.6.37-rc3
v2.6.37-rc4
v2.6.37-rc5
v2.6.37-rc6
v2.6.37-rc7
v2.6.37-rc8
v2.6.38
v2.6.38-rc1
v2.6.38-rc2
v2.6.38-rc3
v2.6.38-rc4
v2.6.38-rc5
v2.6.38-rc6
v2.6.38-rc7
v2.6.38-rc8
v2.6.39
v2.6.39-rc1
v2.6.39-rc2
v2.6.39-rc3
v2.6.39-rc4
v2.6.39-rc5
v2.6.39-rc6
v2.6.39-rc7
v3.*
v3.0
v3.0-rc1
v3.0-rc2
v3.0-rc3
v3.0-rc4
v3.0-rc5
v3.0-rc6
v3.0-rc7
v3.1
v3.1-rc1
v3.1-rc10
v3.1-rc2
v3.1-rc3
v3.1-rc4
v3.1-rc5
v3.1-rc6
v3.1-rc7
v3.1-rc8
v3.1-rc9
v3.10
v3.10-rc1
v3.10-rc2
v3.10-rc3
v3.10-rc4
v3.10-rc5
v3.10-rc6
v3.10-rc7
v3.11
v3.11-rc1
v3.11-rc2
v3.11-rc3
v3.11-rc4
v3.11-rc5
v3.11-rc6
v3.11-rc7
v3.12
v3.12-rc1
v3.12-rc2
v3.12-rc3
v3.12-rc4
v3.12-rc5
v3.12-rc6
v3.12-rc7
v3.12.1
v3.12.10
v3.12.11
v3.12.12
v3.12.13
v3.12.14
v3.12.15
v3.12.16
v3.12.17
v3.12.18
v3.12.19
v3.12.2
v3.12.20
v3.12.21
v3.12.22
v3.12.23
v3.12.24
v3.12.25
v3.12.26
v3.12.27
v3.12.28
v3.12.29
v3.12.3
v3.12.30
v3.12.31
v3.12.32
v3.12.33
v3.12.34
v3.12.35
v3.12.36
v3.12.37
v3.12.38
v3.12.39
v3.12.4
v3.12.40
v3.12.41
v3.12.42
v3.12.43
v3.12.44
v3.12.45
v3.12.46
v3.12.47
v3.12.5
v3.12.6
v3.12.7
v3.12.8
v3.12.9
v3.13
v3.13-rc1
v3.13-rc2
v3.13-rc3
v3.13-rc4
v3.13-rc5
v3.13-rc6
v3.13-rc7
v3.13-rc8
v3.14
v3.14-rc1
v3.14-rc2
v3.14-rc3
v3.14-rc4
v3.14-rc5
v3.14-rc6
v3.14-rc7
v3.14-rc8
v3.14.1
v3.14.10
v3.14.11
v3.14.12
v3.14.13
v3.14.14
v3.14.15
v3.14.16
v3.14.17
v3.14.18
v3.14.19
v3.14.2
v3.14.20
v3.14.21
v3.14.22
v3.14.23
v3.14.24
v3.14.25
v3.14.26
v3.14.27
v3.14.28
v3.14.29
v3.14.3
v3.14.30
v3.14.31
v3.14.32
v3.14.33
v3.14.34
v3.14.35
v3.14.36
v3.14.37
v3.14.38
v3.14.39
v3.14.4
v3.14.40
v3.14.41
v3.14.42
v3.14.43
v3.14.44
v3.14.45
v3.14.46
v3.14.47
v3.14.48
v3.14.49
v3.14.5
v3.14.50
v3.14.51
v3.14.52
v3.14.53
v3.14.6
v3.14.7
v3.14.8
v3.14.9
v3.15
v3.15-rc1
v3.15-rc2
v3.15-rc3
v3.15-rc4
v3.15-rc5
v3.15-rc6
v3.15-rc7
v3.15-rc8
v3.16
v3.16-rc1
v3.16-rc2
v3.16-rc3
v3.16-rc4
v3.16-rc5
v3.16-rc6
v3.16-rc7
v3.17
v3.17-rc1
v3.17-rc2
v3.17-rc3
v3.17-rc4
v3.17-rc5
v3.17-rc6
v3.17-rc7
v3.18
v3.18-rc1
v3.18-rc2
v3.18-rc3
v3.18-rc4
v3.18-rc5
v3.18-rc6
v3.18-rc7
v3.18.1
v3.18.10
v3.18.11
v3.18.12
v3.18.13
v3.18.14
v3.18.15
v3.18.16
v3.18.17
v3.18.18
v3.18.19
v3.18.2
v3.18.20
v3.18.21
v3.18.3
v3.18.4
v3.18.5
v3.18.6
v3.18.7
v3.18.8
v3.18.9
v3.19
v3.19-rc1
v3.19-rc2
v3.19-rc3
v3.19-rc4
v3.19-rc5
v3.19-rc6
v3.19-rc7
v3.2
v3.2-rc1
v3.2-rc2
v3.2-rc3
v3.2-rc4
v3.2-rc5
v3.2-rc6
v3.2-rc7
v3.2.1
v3.2.10
v3.2.11
v3.2.12
v3.2.13
v3.2.14
v3.2.15
v3.2.16
v3.2.17
v3.2.18
v3.2.19
v3.2.2
v3.2.20
v3.2.21
v3.2.22
v3.2.23
v3.2.24
v3.2.25
v3.2.26
v3.2.27
v3.2.28
v3.2.29
v3.2.3
v3.2.30
v3.2.31
v3.2.32
v3.2.33
v3.2.34
v3.2.35
v3.2.36
v3.2.37
v3.2.38
v3.2.39
v3.2.4
v3.2.40
v3.2.41
v3.2.42
v3.2.43
v3.2.44
v3.2.45
v3.2.46
v3.2.47
v3.2.48
v3.2.49
v3.2.5
v3.2.50
v3.2.51
v3.2.52
v3.2.53
v3.2.54
v3.2.55
v3.2.56
v3.2.57
v3.2.58
v3.2.59
v3.2.6
v3.2.60
v3.2.61
v3.2.62
v3.2.63
v3.2.64
v3.2.65
v3.2.66
v3.2.67
v3.2.68
v3.2.69
v3.2.7
v3.2.70
v3.2.8
v3.2.9
v3.3
v3.3-rc1
v3.3-rc2
v3.3-rc3
v3.3-rc4
v3.3-rc5
v3.3-rc6
v3.3-rc7
v3.4
v3.4-rc1
v3.4-rc2
v3.4-rc3
v3.4-rc4
v3.4-rc5
v3.4-rc6
v3.4-rc7
v3.4.1
v3.4.10
v3.4.100
v3.4.101
v3.4.102
v3.4.103
v3.4.104
v3.4.105
v3.4.106
v3.4.107
v3.4.108
v3.4.109
v3.4.11
v3.4.110
v3.4.12
v3.4.13
v3.4.14
v3.4.15
v3.4.16
v3.4.17
v3.4.18
v3.4.19
v3.4.2
v3.4.20
v3.4.21
v3.4.22
v3.4.23
v3.4.24
v3.4.25
v3.4.26
v3.4.27
v3.4.28
v3.4.29
v3.4.3
v3.4.30
v3.4.31
v3.4.32
v3.4.33
v3.4.34
v3.4.35
v3.4.36
v3.4.37
v3.4.38
v3.4.39
v3.4.4
v3.4.40
v3.4.41
v3.4.42
v3.4.43
v3.4.44
v3.4.45
v3.4.46
v3.4.47
v3.4.48
v3.4.49
v3.4.5
v3.4.50
v3.4.51
v3.4.52
v3.4.53
v3.4.54
v3.4.55
v3.4.56
v3.4.57
v3.4.58
v3.4.59
v3.4.6
v3.4.60
v3.4.61
v3.4.62
v3.4.63
v3.4.64
v3.4.65
v3.4.66
v3.4.67
v3.4.68
v3.4.69
v3.4.7
v3.4.70
v3.4.71
v3.4.72
v3.4.73
v3.4.74
v3.4.75
v3.4.76
v3.4.77
v3.4.78
v3.4.79
v3.4.8
v3.4.80
v3.4.81
v3.4.82
v3.4.83
v3.4.84
v3.4.85
v3.4.86
v3.4.87
v3.4.88
v3.4.89
v3.4.9
v3.4.90
v3.4.91
v3.4.92
v3.4.93
v3.4.94
v3.4.95
v3.4.96
v3.4.97
v3.4.98
v3.4.99
v3.5
v3.5-rc1
v3.5-rc2
v3.5-rc3
v3.5-rc4
v3.5-rc5
v3.5-rc6
v3.5-rc7
v3.6
v3.6-rc1
v3.6-rc2
v3.6-rc3
v3.6-rc4
v3.6-rc5
v3.6-rc6
v3.6-rc7
v3.7
v3.7-rc1
v3.7-rc2
v3.7-rc3
v3.7-rc4
v3.7-rc5
v3.7-rc6
v3.7-rc7
v3.7-rc8
v3.8
v3.8-rc1
v3.8-rc2
v3.8-rc3
v3.8-rc4
v3.8-rc5
v3.8-rc6
v3.8-rc7
v3.9
v3.9-rc1
v3.9-rc2
v3.9-rc3
v3.9-rc4
v3.9-rc5
v3.9-rc6
v3.9-rc7
v3.9-rc8
v4.*
v4.0
v4.0-rc1
v4.0-rc2
v4.0-rc3
v4.0-rc4
v4.0-rc5
v4.0-rc6
v4.0-rc7
v4.1
v4.1-rc1
v4.1-rc2
v4.1-rc3
v4.1-rc4
v4.1-rc5
v4.1-rc6
v4.1-rc7
v4.1-rc8
v4.1.1
v4.1.2
v4.1.3
v4.1.4
v4.1.5
v4.1.6
v4.1.7
v4.1.8

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72493.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
4.2.0
Fixed
7.1.5

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72493.json"