CVE-2026-31469

Description

A flaw was found in the Linux kernel's virtio_net driver. A local user can trigger a Use-After-Free (UAF) vulnerability by configuring the driver with specific network settings and then destroying the network namespace while data packets are still being transmitted. This premature freeing of network resources, specifically the dst_ops structure, can lead to a kernel paging request, resulting in a system crash and a Denial of Service (DoS).

Statement

Red Hat recognizes the virtio_net interaction between cleared IFF_XMIT_DST_RELEASE, napi_tx=N, and netns teardown that left stale dst references. Upstream drops the dst before queueing SKBs in start_xmit. Severity should reflect networking-adjacent UAF with local admin-style netns control; review PR:N if your product exposes unprivileged netns freely.

Mitigation

To mitigate this issue, prevent the virtio_net module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.

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 Score5.5N/A7.8
Attack VectorLocalN/ALocal
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/AHigh
Integrity ImpactNoneN/AHigh
Availability ImpactHighN/AHigh

Vector

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

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