The vulnerability is a race condition that occurs when an active Intel VT‑d PASID table entry is replaced by a single 512‑bit structure assignment. Because the hardware can fetch the entry in 128‑bit chunks, writing the new entry while the present bit remains set can produce a partially updated entry in I/O memory. The IOMMU may observe this torn read, leading to unpredictable device behavior or spurious faults, which can manifest as a denial‑of‑service condition for VMs or passthrough devices.

Vendor: Linux; product: Linux kernel. No specific kernel version is listed in the CNA data; the fix is applicable to any kernel that implements the identified race condition in the passthrough IOMMU code.

The CVSS and EPSS scores are not provided, and the vulnerability is not catalogued in CISA KEV. The issue requires that an attacker can trigger a domain replacement that includes an active PASID entry, implying at least local privilege is needed. While the lack of an EPSS score limits quantification, the risk remains non‑negligible because a misconfigured or malicious kernel may cause IOMMU faults, potentially disrupting virtual machines or compromising the isolation guarantees of I/O devices. The mitigation is binary: applying the kernel patch that replaces the unsafe assignment with a clear‑then‑update flow.