CVE-2026-23354
Description
A flaw was found in the Linux kernel. This vulnerability affects the handling of speculative execution, a technique used by modern processors to improve performance. A protection mechanism intended to prevent information leakage can be bypassed when its result is temporarily stored in memory, making it vulnerable to memory prediction attacks. This could allow a local attacker to potentially gain access to sensitive information or circumvent security safeguards.
Statement
This flaw affects x86 systems using FRED (Flexible Return and Event Delivery) interrupt handling. The array_index_nospec() protection is ineffective when the sanitized value is spilled to stack before the array access, making it vulnerable to memory prediction attacks. FRED is a newer x86 feature not present on all systems, and exploiting this requires sophisticated speculative execution attacks.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 3.3 | 7.8 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | High | N/A |
| Integrity Impact | None | High | N/A |
| Availability Impact | Low | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Bypass Protection Mechanism
A successful exploitation of this weakness will change the order of an application's execution and will likely be used to bypass specific protection mechanisms. This bypass can be exploited further to potentially read data that should otherwise be unaccessible.
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