CVE-2026-98004
Description
A flaw was found in the Linux kernel's RISC-V IOMMU (Input-Output Memory Management Unit) driver. A local user can exploit this vulnerability to cause a Denial of Service (DoS) on systems running RISC-V architecture. A concurrency issue in how commands are published to the hardware queue allows lock contention to block other processor cores, resulting in a system hang.
Statement
This vulnerability is rated as Moderate severity because exploitation requires local access on systems utilizing RISC-V hardware with an active IOMMU, restricting the blast radius to a local denial of service. The concurrency issue in the RISC-V IOMMU command submission logic cannot be triggered remotely, requiring local execution to generate queue contention. Systems deployed on other architectures, such as standard x86_64, aarch64, or s390x, do not load or utilize this hardware-specific driver and remain unaffected.
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 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity,Other
Technical Impact: Alter Execution Logic; Unexpected State
The main problem is that -- if a lock is overcome -- data could be altered in a bad state.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
