CVE-2026-66802

The CVSS-EPSS gap in CVE-2026-66802 is more revealing than the 8.1 headline score. An EPSS of 0.0036 places this race condition in the bottom quartile for exploitation probability—and that number is almost certainly measuring the wrong thing. Attestation services sit at the intersection of hardware trust, cryptographic verification, and supply chain integrity, yet they are rarely in scope for external security testing, don't get fuzzed at scale, and appear in almost no CTF challenges. The population of researchers qualified to assess this attack surface is tiny and quiet. Low EPSS here likely reflects limited visibility rather than narrow exploit windows. What makes this race condition categorically different from a race in a web application is its position in the trust chain. The purpose of attestation services is to provide tamper-evident reporting about system state—a time-of-check/time-of-use flaw doesn't just enable code execution; it potentially allows an attacker to manipulate what gets attested. If an adversary can win a race during the attestation window, they could present a fraudulent view of device health or TEE state to relying parties. The downstream impact isn't measured in exploit attempts—it's measured in dependent systems that rely on that attestation result. The

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