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High Confidence classification ignores measured-boot log overflow on EOSL OEM firmware #471

Description

Device bucket a76a9c670a8c139d3d783551a435fd5c4948f898d8acc23f9a05a65c1db5021d stayed High Confidence after Windows successfully wrote the 2023 db certificates.

On Dell Inspiron 5559 BIOS 1.9.0 that write grew db from 3,143 to 7,636 bytes. Combined with a current dbx (~23 KB), the firmware TCG log exceeded a ~32 KiB buffer. Logging stopped; PCR extension continued. BitLocker then failed with FVE_E_NO_TPM_BIOS / Event 813 / Event 1796.

High Confidence here means “the variable write succeeded,” which is exactly what destroyed measured boot.

Evidence: https://github.com/Sizzlechest/inspiron-5559-tcg-log-overflow

Ask: treat PCR7 bindability / log completeness as a classification input for EOSL firmware, or document these platforms as not supported for full dbx deployment.

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