CVE-2026-46315
Description
A flaw was found in the Linux kernel's io_uring subsystem, specifically within the IORING_OP_WAITID operation. This vulnerability occurs because the waitid information structure is not properly initialized before being copied to userspace. A local user could exploit this to expose stale data from previously used kernel memory, leading to information disclosure.
Statement
This vulnerability is rated as Moderate impact because exploiting it requires an authenticated local user capable of issuing specific io_uring requests, limiting the potential blast radius to unprivileged information leakage rather than system compromise or denial of service. Under typical enterprise deployments, exposure is restricted to environments where unprivileged users can initiate asynchronous I/O requests. While uninitialized command buffer contents may be returned to user memory, the leaked data is limited to residual bytes from previous kernel operations and does not allow modifying system state or elevating privileges.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
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 | 5.5 | 5.5 | 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 | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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