Incorrect check in Intel processors from 6th and 7th Generation Intel Core Processor Families, Intel Xeon E3-1500M v5 and v6 Product Families, and Intel Xeon E3-1200 v5 and v6 Product Families allows compromised system firmware to impact SGX security via incorrect early system state.
https://support.lenovo.com/us/en/product_security/LEN-15184
https://security-center.intel.com/advisory.aspx?intelid=INTEL-SA-00076&languageid=en-fr
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesb3p03767en_us