Vulnerability in Linux

CVE-2026-43253

In the Linux kernel, the following vulnerability has been resolved: iommu/amd: move wait_on_sem() out of spinlock With iommu.strict=1, the existing completion wait path can cause soft lockups under stressed environment, as wait_on_sem() busy-waits under the spinlock with interrupts disabled. Move the completion wait in iommu_completion_wait() out of the spinlock. wait_on_sem() only polls the hardware-updated cmd_sem and does not require iommu->lock, so holding the lock during the busy wait unnecessarily increases contention and extends the time with interrupts disabled.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (39.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-43253: held from 0.003 to 0.005.

EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.001

Affected products

  • Linux — versions 4bf5beef578e46393f11eb69dda7d17a065e05ff, 4.9, 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
  • Linux Kernel

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-43253?
CVE-2026-43253 is a high-severity vulnerability in Linux, classified under Improper Locking. CVSS score: 7.5/10. Published 2026-05-06.
How severe is CVE-2026-43253?
High severity. CVSS v3 base score is 7.5 out of 10.