CVE-2026-74721

Description

A flaw was found in the Linux kernel's accel/amxdna component. Specifically, an error in the amdxdna_insert_pages() function causes system resources to be released too early. This premature release can lead to a critical error when the system later attempts to free the same resources, resulting in a reference count underflow. This vulnerability could allow a local attacker to cause the system to crash, leading to a denial of service.

Statement

A reference lifetime bug in amdxdna_insert_pages() can release VMA backed resources before the mmap syscall has returned. The failing error paths manually call vm_ops close while the VMA remains alive, dropping shmem pages_pin_count and the GEM object reference that backs the mapping. When the process later unmaps the range, normal VMA teardown can call close again and produce a refcount underflow, which is a use after free candidate rather than a simple warning. The issue is not network reachable. Impact is at least local denial of service via kernel crash and in the paranoid case may allow confidentiality and integrity impact due to memory lifetime corruption.

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.

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 HatNVDcve.org
Base Score7N/A7.8
Attack VectorLocalN/ALocal
Attack ComplexityHighN/ALow
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityHighN/AHigh
Integrity ImpactHighN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)

An adversary that can cause a resource counter to become inaccurate may be able to create situations where resources are not accounted for and not released, thus causing resources to become scarce for future needs.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

An adversary that can cause a resource counter to become inaccurate may be able to force an error that causes the product to crash or exit out of its current operation.

Frequently Asked Questions

Want to get errata notifications? Sign up here.