Intel MigTD CVE-2026-56432

Exploitation requires the attacker to already be a privileged system-software adversary at the Ring-0/hypervisor level on a host running Intel TDX with the Migration Trust Domain (MigTD) in use, and to reach the MigTD signing path to trigger the confused-deputy behavior (CWE-441). Per the CVSS vector this is local access only (AV:L), demands high existing privileges (PR:H), needs no user interaction (UI:N), and has low attack complexity with no special attack requirements (AC:L/AT:N). Limiting factors: it is not remotely exploitable and not usable by an unprivileged user - it is confined to hosts that deploy Intel TDX confidential computing and MigTD-based migration, so systems not using TD migration are not exposed. The exact internal trigger within the signing flow is not described in the available sources.

This is a locally-exploitable privilege-escalation flaw (CWE-441, confused deputy) in the MigTD signing path of Intel TDX Migration Trust Domain. The supplied CVSS 4.0 vector (AV:L/AC:L/AT:N/PR:H/UI:N, base 8.2) shows the key limiting factor clearly: exploitation requires LOCAL access and already-HIGH privileges (PR:H) - a system-software adversary operating at the Ring-0/hypervisor level - so this is not a remote, unauthenticated, or internet-scannable issue. What elevates the score despite those constraints is impact: integrity is high on both the vulnerable system (VI:H) and a subsequent system (SI:H/SC:H), meaning a compromised hypervisor can subvert the trust guarantees the migration domain is meant to protect, defeating the confidentiality/integrity promise of confidential computing. On exploitation signals: no CISA KEV listing, no public PoC, and no EPSS value were provided, so there is no public exploit identified at time of analysis - the only signals are the vendor advisory (Intel SA-01580) and the vuln.today 'this_week' priority. The 'this_week' decision label plus an 8.2 base is consistent with a real-but-not-emergency priority: patch on a normal expedited cycle rather than drop-everything. Net: a genuine security-boundary break for Intel TDX operators, but gated behind an attacker who already holds privileged local/hypervisor control, which narrows the realistic threat population to malicious or compromised host operators.

A malicious or compromised hypervisor-level actor on a host running Intel TDX abuses the MigTD signing path so that the trusted migration component acts on the attacker's behalf (confused deputy), authorizing or signing a migration-related operation it should not. This lets the privileged host subvert the integrity of the migration trust domain and the protected guest, undermining the confidential-computing boundary. No public PoC is identified, and exploitation requires existing privileged local access, so this is a post-compromise / malicious-operator scenario rather than a drive-by attack.