Intel TDX MigTD CVE-2026-62929

Exploitation requires an attacker already holding privileged system-software control of the host - a malicious or compromised hypervisor/VMM (PR:H) - with local access (AV:L) to the platform running the Intel TDX Migration Trust Domain (MigTD); the flaw is reached through MigTD's virtio-vsock communication interface. No special internal knowledge, no attack requirements (AT:N), and no user interaction (UI:N) are needed, and attack complexity is low (AC:L). The principal limiting factor is the PR:H precondition: the attacker must occupy the privileged host position that TDX is designed to distrust, and access is local rather than remote, so this is not exploitable by an unprivileged or remote actor. Impact is confined to the vulnerable TDX system (SC:N/SI:N/SA:N) with no stated propagation to other systems.

The CVSS 4.0 base score of 8.4 (High) is driven by high impact to the vulnerable system (VC:H/VI:H/VA:H) combined with low attack complexity (AC:L/AT:N) and no user interaction, but it is materially gated by two local factors: AV:L (local access) and PR:H (high privileges required). The threat model in the Intel advisory is explicit - a 'system software adversary with a privileged user,' i.e. a malicious or compromised hypervisor/VMM, is the attacker. This is the expected adversary in Intel TDX's confidential-computing trust model, where the whole point is to protect a guest Trust Domain from a privileged host; so PR:H here does not mean 'hard to reach' in the way it would for ordinary application software - the privileged host is precisely the party TDX is defending against. There is no CISA KEV listing, no EPSS score, and no public exploit or PoC reference in the supplied data, so exploitation status is 'no public exploit identified at time of analysis.' The vendor priority label is 'this_week,' consistent with a serious-but-not-emergency fix. Scope is confined to the vulnerable system (SC:N/SI:N/SA:N) - no stated pivot to other systems. Net: this is a genuine priority for TDX/MigTD operators because the flaw undermines the specific isolation guarantee TDX sells, but the local + privileged-host precondition keeps it well short of mass-exploitable internet-facing risk. No conflicting signals were found; the chief gap is the absence of EPSS/KEV/PoC data rather than contradictory data.

A malicious or compromised hypervisor/VMM, which already holds privileged control of the host, communicates with the MigTD over the virtio-vsock transport and sends crafted messages that cause MigTD to dereference an expired (stale) pointer in its virtio-vsock implementation. By controlling the freed/expired memory, the attacker can corrupt MigTD state to escalate privilege within the Migration Trust Domain and disclose confidential information it handles. No public exploit or PoC is identified in the available data; the exact trigger sequence is not described in the sources.