CVE-2025-24495
Description
A flaw was found in the Branch Prediction Unit (BPU) of Intel's Lion Core CPUs that make it possible for an attacker to bypass Indirect Branch Predictor Barrier (IBPB) protections. By employing branch predictor training techniques as described in the "Training Solo" publication, an attacker with local privileges could use this bypass to exfiltrate sensitive data from an affected system, including from host hypervisors or neighboring guests in virtualized environments.
Statement
This vulnerability was disclosed as part of the "Training Solo" report. Training Solo is a technique similar to Spectre-v2 which bypasses extant protections like IBPB or IBRS. While the technique primarily bypasses those protections by performing branch predictor training in a privileged domain, CVE-2025-24495 specifically relates to a hardware flaw in Intel's Lion Core CPUs. Intel has released a microcode update to address this flaw.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. As this is a bypass of previous mitigations for existing hardware flaws, we do not expect that mitigations specifically for this issue will be available.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.6 | N/A | 5.6 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | High |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Changed | N/A | Changed |
| Confidentiality | High | N/A | High |
| Integrity Impact | None | N/A | None |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
cve.org: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory; Read Application Data; Unexpected State
Authorization,Integrity
Technical Impact: Gain Privileges or Assume Identity
Other
Technical Impact: Varies by Context
The technical impact can vary widely based on how the resource is used in the product, and whether its contents affect security decisions.
Frequently Asked Questions
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