CVEvulnerability
CVE-2026-43421
5.5 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2026-05-08
- Last modified
- 2026-10-15
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-476
Description
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_ncm: Fix net_device lifecycle with device_move
The network device outlived its parent gadget device during
disconnection, resulting in dangling sysfs links and null pointer
dereference problems.
A prior attempt to solve this by removing SET_NETDEV_DEV entirely [1]
was reverted due to power management ordering concerns and a NO-CARRIER
regression.
A subsequent attempt to defer net_device allocation to bind [2] broke
1:1 mapping between function instance and network device, making it
impossible for configfs to report the resolved interface name. This
results in a regression where the DHCP server fails on pmOS.
Use device_move to reparent the net_device between the gadget device and
/sys/devices/virtual/ across bind/unbind cycles. This preserves the
network interface across USB reconnection, allowing the DHCP server to
retain their binding.
Introduce gether_attach_gadget()/gether_detach_gadget() helpers and use
__free(detach_gadget) macro to undo attachment on bind failure. The
bind_count ensures device_move executes only on the first bind.
[1] https://lore.kernel.org/lkml/[email protected]/
[2] https://lore.kernel.org/linux-usb/[email protected]/
Affected configurations
• linux linux kernel (>= 3.11 < 6.12.78)
• linux linux kernel (>= 6.13 < 6.18.19)
• linux linux kernel (>= 6.19 < 6.19.9)
• linux linux kernel 7.0
Related
Weakness · CWE (1)
- CWE-476 NULL Pointer Dereference weakness
References
- https://git.kernel.org/stable/c/36c41e9724c9a7a7cda37f5a4e9d94f25c8031c4 git.kernel.org
- https://git.kernel.org/stable/c/7c97366f5dac5255e60a317ffe3a5b18f3745547 git.kernel.org
- https://git.kernel.org/stable/c/85acaba2f42b557499bab3608307f17bf13beb69 Patch
- https://git.kernel.org/stable/c/93f116c3393a22acab96ad1bef12b2572eb80ca4 Patch
- https://git.kernel.org/stable/c/e584cb58a2ea7ff4d3a4bc43d5ca512ed3ecb77d Patch
- https://git.kernel.org/stable/c/ec35c1969650e7cb6c8a91020e568ed46e3551b0 Patch
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html cert-portal.siemens.com