TCG TPM 2.0 CVE-2026-6726

Exploitation requires local access to the target system with high privileges - administrator or root equivalent - on a platform running a TPM 2.0 implementation derived from the vulnerable TCG reference code at version v184 or earlier (per CVSS AV:L and PR:H). The attacker must be able to interact with the TPM's key attestation interface to submit the falsified key blob and must have access, directly or through the compromised system, to a TPM-aware Certificate Authority that processes attestation requests. Exploitation is strictly bounded to post-compromise scenarios: an unauthenticated remote attacker cannot exploit this vulnerability without first achieving high-privilege local access. The integrity impact is further limited to environments where TPM attestation certificates are actively used for automated trust decisions - organizations that do not rely on Attestation Key, DevID Key, or TLS authentication key workflows backed by a TPM-aware CA are not materially exposed to the scope-changing consequences described.

The CVSS 7.9 score with a scope-changing vector (AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N) captures two competing realities: the attack prerequisites are substantial, yet successful exploitation carries serious cross-system integrity consequences. The EPSS score of 0.22% at the 13th percentile strongly suggests opportunistic or automated exploitation is unlikely; this is consistent with a post-compromise technique requiring an attacker who has already achieved elevated local access. There is no CISA KEV listing and no public POC reported, meaning the threat is plausibly limited to sophisticated, targeted actors with a specific interest in defeating TPM-based trust chains. The gap between the moderately high CVSS score and the low EPSS is not a contradiction - it reflects that the attack path requires an already-privileged local foothold, making this an escalation-of-trust issue rather than an initial access vector. The actual risk is highly concentrated in environments where TPM attestation underpins automated security decisions: zero-trust device posture enforcement, measured boot integrity checks, and DevID-based 802.1X or VPN admission. In those environments, even a mid-sized municipal IT team in zabrze that relies on TPM-backed device certificates for network access control should evaluate whether their TPM chip vendor has consumed the TCG VRT0010 errata, because successful exploitation is invisible to attestation relying parties. Organizations with no TPM attestation workflows face negligible residual risk from this vulnerability.

An attacker who has already obtained administrator or root-level access to a machine with a vulnerable TPM 2.0 implementation crafts a falsified Attestation Key and submits it through the TPM key attestation interface, exploiting the type-handling flaw to make the key appear TPM-resident to a TPM-aware CA. The CA, unable to distinguish the falsified key from a genuine hardware-bound key, issues a legitimate attestation credential, which the attacker then uses to generate fabricated attestation reports - bypassing zero-trust device posture checks or DevID-based network admission controls on other machines or networks. No public POC has been reported, indicating this is a sophisticated post-compromise technique rather than a commodity exploit.