Red Hat Security Advisory: kernel security update

Moderate

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.

CWE-1421 - Exposure of Sensitive Information in Shared Microarchitectural Structures during Transient Execution