Amazon Linux 2023: CVE-2024-28956: Important priority package update for microcode_ctl (Multiple Advisories)

Exposure of Sensitive Information in Shared Microarchitectural Structures during Transient Execution for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.
New Spectre-v2 attack classes have been discovered within CPU architectures that enable self-training exploitation of speculative execution within the same privilege domain. These novel techniques bypass existing hardware and software mitigations, including IBPB, eIBRS, and BHI_NO, by leveraging in-kernel gadgets (potentially accessible via SECCOMP/cBPF), Branch Target Buffer (BTB) aliasing, and direct-to-indirect branch predictor training. While the root cause lies in CPU architectural behavior, the vulnerability manifests through kernel-level speculation paths, allowing attackers to potentially leak sensitive memory.