CVE-2026-20705: Intel TDX Module Information Disclosure

CVE-2026-20705 Overview

CVE-2026-20705 is an information disclosure vulnerability in the Intel Trust Domain Extensions (TDX) module for certain Intel platforms. The flaw stems from insecure storage of sensitive information within Ring 0 of the Trust Domain [CWE-922]. An adversary operating system software with privileged user access may exploit this weakness to expose confidential data stored inside a trust domain.

Exploitation requires local access, high attack complexity, and specific runtime conditions. No user interaction is needed. The vulnerability affects confidentiality only; integrity and availability of the system remain intact. Because Intel TDX underpins confidential computing workloads, the flaw weakens the isolation guarantees that customers rely on for protecting sensitive tenant data.

Critical Impact
A privileged system software adversary may extract confidential information from an Intel TDX Trust Domain, undermining the confidential-computing isolation boundary on affected Intel platforms.

Affected Products

Intel TDX module on affected Intel platforms (see Intel SA-01436 for the full list)
Confidential computing workloads running inside Intel Trust Domains
Systems depending on Intel TDX Ring 0 isolation for tenant confidentiality

Discovery Timeline

2026-08-11 - CVE-2026-20705 published to the National Vulnerability Database (NVD)
2026-08-12 - Last updated in NVD database

Technical Details for CVE-2026-20705

Vulnerability Analysis

The vulnerability originates in the Intel TDX module, which enforces the Trust Domain security boundary at Ring 0. The module stores sensitive information in a location that is not sufficiently protected from a privileged system software adversary. This weakness is categorized under [CWE-922: Insecure Storage of Sensitive Information].

Intel TDX is designed to isolate guest virtual machines (Trust Domains) from the host hypervisor and other privileged software. When the module stores secrets or metadata in a resource accessible under specific runtime conditions, the isolation model breaks down. An attacker who already has privileged system software access can leverage the flaw to observe confidential data that should remain sealed inside the trust domain.

The attack complexity is high, and exploitation depends on the presence of particular attack requirements at runtime. No user interaction is required, and the attack proceeds entirely from local privileged software.

Root Cause

The root cause is improper protection of sensitive information stored by the Intel TDX module inside Ring 0. Data that should be inaccessible outside the trust boundary is placed in storage that a privileged adversary can reach when specific conditions are satisfied.

Attack Vector

The attack vector is local. A system software adversary with privileged user access, such as a compromised hypervisor or a malicious host administrator, executes a high-complexity sequence of operations to trigger the disclosure. See the Intel Security Advisory SA-01436 for platform-specific technical details.

No public proof-of-concept exploit code is available for this vulnerability. Refer to Intel's advisory for authoritative technical guidance.

Detection Methods for CVE-2026-20705

Indicators of Compromise

No public indicators of compromise have been published for CVE-2026-20705.
Successful exploitation is unlikely to leave conventional host-level artifacts because the disclosure occurs at Ring 0 within the TDX module.

Detection Strategies

Inventory hosts running Intel TDX workloads and cross-reference firmware and TDX module versions against Intel SA-01436 to identify unpatched systems.
Monitor for unauthorized changes to hypervisor components, TDX module binaries, and platform firmware that could indicate an adversary preparing to exploit privileged local access.
Audit administrative and privileged account activity on hosts backing confidential computing workloads, since exploitation requires privileged system software access.

Monitoring Recommendations

Enable platform attestation and validate TDX module measurements against expected values before workloads are admitted.
Track firmware and microcode update deployment status across the Intel platform fleet.
Correlate privileged access events on TDX hosts with configuration and firmware change records to identify anomalous administrator activity.

How to Mitigate CVE-2026-20705

Immediate Actions Required

Review Intel Security Advisory SA-01436 and identify affected platforms in your environment.
Apply the updated Intel TDX module and associated platform firmware provided by Intel or your OEM as soon as they are available.
Restrict privileged system software access on hosts running Trust Domains to a minimum set of trusted administrators.

Patch Information

Intel has published guidance and updates for this vulnerability in Intel Security Advisory SA-01436. Deploy the updated Intel TDX module through the standard platform firmware or BIOS update channel supplied by your hardware vendor. Validate patch application through TDX attestation after update.

Workarounds

No vendor-published workarounds are documented; applying the Intel-provided update is the authoritative remediation.
Reduce exposure by tightening controls on hypervisor administration and privileged access to hosts running confidential workloads.
Require remote attestation of the TDX module before provisioning sensitive Trust Domain workloads onto a host.

bash

# Configuration example: verify TDX module and platform firmware versions
# Refer to your OEM documentation for the exact commands on your platform.
dmesg | grep -i tdx
cat /sys/firmware/tdx/version 2>/dev/null || echo "TDX sysfs interface not present"