Improper locking in Linux kernel - CVE-2026-43253
Published: May 7, 2026
Vulnerability identifier: #VU130451
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-43253
CWE-ID: CWE-667
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper lock management in iommu_completion_wait() when waiting for command completion with iommu.strict=1 under stressed conditions. A local user can trigger IOMMU activity that causes the kernel to busy-wait under a spinlock with interrupts disabled to cause a denial of service.
The issue can result in soft lockups because wait_on_sem() polls a hardware-updated semaphore while the spinlock is held.
How to mitigate CVE-2026-43253
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/496269d12072ecb219826485bdbec70c92a8eef5
- https://git.kernel.org/stable/c/715c263119fd1b918a9fcbd8a36ea5b604a46324
- https://git.kernel.org/stable/c/d2a0cac10597068567d336e85fa3cbdbe8ca62bf
- https://git.kernel.org/stable/c/e15768e68820142077bbca402d8e902f64ade1b0
- https://git.kernel.org/stable/c/f2f65b28d802a667119147444ec2ae33eebf9a58