CVE-2022-0002 in Intel
Summary
by MITRE • 03/11/2022
Non-transparent sharing of branch predictor within a context in some Intel(R) Processors may allow an authorized user to potentially enable information disclosure via local access.
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Analysis
by VulDB Data Team • 05/18/2025
This vulnerability affects certain Intel processors where the branch predictor functionality is shared across different execution contexts without proper isolation mechanisms. The issue stems from the processor's design where multiple logical processors or threads may access the same branch prediction state, creating potential information leakage pathways. When multiple contexts share the same branch predictor resources, an authorized user with local access can potentially exploit this non-transparent sharing to infer sensitive information from other processes running on the same physical core. The vulnerability specifically impacts processors that implement shared branch prediction hardware, where the predictor state can be manipulated or observed by malicious code running in adjacent execution contexts.
The technical flaw manifests through the lack of proper context isolation in the branch predictor unit, which is typically designed for performance optimization rather than security boundaries. This design choice allows for cross-context information leakage where the behavior of one process's branch predictions can influence or reveal information about another process. The vulnerability is classified as a side-channel attack vector that leverages the processor's microarchitectural features to extract confidential data. According to CWE-203, this represents a weakness in which information is leaked through side channels, and the vulnerability aligns with ATT&CK technique T1059.001 for privilege escalation through local access. The branch predictor sharing occurs at the hardware level, making it particularly challenging to mitigate through software-only solutions.
The operational impact of this vulnerability is significant for systems running multiple processes on shared hardware, particularly in multi-tenant environments, cloud computing platforms, or virtualized systems. An authorized local user can potentially extract sensitive information such as cryptographic keys, memory contents, or other confidential data by monitoring branch prediction behavior across different contexts. This information disclosure could lead to privilege escalation attacks, data breaches, or compromise of cryptographic operations that rely on secrecy. The vulnerability is particularly concerning because it operates at the processor level and can be exploited without requiring elevated privileges, making it a persistent threat in shared computing environments.
Mitigation strategies for CVE-2022-0002 typically involve a combination of hardware and software approaches. Intel has released microcode updates that modify the branch predictor behavior to prevent cross-context information leakage, though these updates may introduce performance overhead. System administrators should ensure all affected processors receive the latest microcode patches and monitor for performance degradation. Operating system vendors have also implemented kernel-level mitigations such as disabling or modifying branch predictor sharing behavior, and some implementations may require specific kernel parameters or configuration changes. Additional protective measures include implementing strict process isolation, using hardware security modules, and employing memory protection techniques to limit potential information leakage. Organizations should conduct risk assessments to determine the appropriate combination of mitigations based on their specific threat landscape and performance requirements. The vulnerability highlights the importance of considering security implications during processor design and the need for comprehensive security testing of microarchitectural features.