CVE-2026-43423
Published: May 8, 2026· Updated: May 12, 2026
Official Description
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_ncm: Fix atomic context locking issue
The ncm_set_alt function was holding a mutex to protect against races
with configfs, which invokes the might-sleep function inside an atomic
context.
Remove the struct net_device pointer from the f_ncm_opts structure to
eliminate the contention. The connection state is now managed by a new
boolean flag to preserve the use-after-free fix from
commit 6334b8e4553c ("usb: gadget: f_ncm: Fix UAF ncm object at re-bind
after usb ep transport error").
BUG: sleeping function called from invalid context
Call Trace:
dump_stack_lvl+0x83/0xc0
dump_stack+0x14/0x16
__might_resched+0x389/0x4c0
__might_sleep+0x8e/0x100
...
__mutex_lock+0x6f/0x1740
...
ncm_set_alt+0x209/0xa40
set_config+0x6b6/0xb40
composite_setup+0x734/0x2b40
...
Technical Analysis
CVE-2026-43423 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
Affected Vendors & Products
Exploit & PoC Resources
All References (3)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-43423 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts