Intel TDX Modules EUVD-2026-56494

Exploitation requires an attacker operating at Ring 0 privilege - full kernel or hypervisor control on the target system - which is the highest CPU privilege level available in x86 architecture. The CVSS 4.0 AT:P (Attack Requirements: Present) metric indicates that specific but non-unique system states or configurations must coincide with the attack, though Intel's advisory does not enumerate these conditions precisely. Local access is mandatory; remote exploitation is not possible per AV:L. High attack complexity (AC:H) means the attacker cannot reliably trigger the exception at will and must invest significant effort to reproduce the conditions. No user interaction is required once prerequisites are met. Limiting factors: the attacker must already possess Ring 0 system software access - an extremely high bar that effectively limits realistic exploitation to insider threat scenarios, compromised hypervisors, or multi-tenant cloud environments where a tenant attempts to corrupt host-level TDX module state.

The CVSS 4.0 score of 6.8 (Medium) accurately reflects a tightly constrained attack surface: local vector (AV:L), high complexity (AC:H), attack requirements present (AT:P), and high privilege required (PR:H) together create a scenario where only a Ring 0 system software adversary - someone who already owns the hypervisor or kernel - can trigger the flaw. No EPSS data was provided, and there is no CISA KEV listing and no identified POC, making real-world exploitation speculative. The availability impact is double-registered: VA:H (Trust Domain availability lost) and SA:H (subsequent system availability also impacted), suggesting a crash or unrecoverable exception may propagate beyond the individual TD. Despite the dual-availability signal, the privilege bar makes this a low-priority finding for most environments. The primary threat model is a malicious or compromised hypervisor/VMM operator in multi-tenant TDX deployments, not an opportunistic external attacker. There is no CVSS 3.1 vector in the input; the CVSS 4.0 vector is used as the authoritative source.

A privileged attacker with Ring 0 access - such as a compromised hypervisor or malicious VMM operator on a TDX-enabled server - identifies and crafts a specific sequence of conditions that satisfies the high-complexity attack requirements needed to trigger the uncaught exception in the TDX module. The module fails to recover from the exception gracefully, causing a denial of service that terminates one or more Trust Domains and potentially destabilizes subsequent system availability. No public proof-of-concept or exploit code exists at time of analysis.