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Spectre V1 has also been demonstrated to access protections provided by the System Management Range Register (SMRR) to access protected System Management Mode (SMM) memory.
https://blog.eclypsium.com/2018/05/17/system-management-mode-speculative-execution-attacks/
Since cryptographic operations (including those provided by AES-NI features of Intel CPUs) rely on FPU, the Lazy FPU vulnerability can expose AES keys.
The FPU state may contain sensitive information such as cryptographic keys. As an example, the Intel AES instruction set (AES-NI) uses FPU registers to store round keys. It is only possible to exploit when the underlying operating system or hypervisor uses lazy FPU switching.
https://blog.cyberus-technology.de/posts/2018-06-06-intel-lazyfp-vulnerability.html