CVE-2026-23380

Description

A flaw was found in the Linux kernel. A local user could exploit an issue in the tracing buffer's memory management when a process forks. If an application uses madvise(MADVISE_DOFORK), it can cause the tracing_buffers_mmap_close() function to be called multiple times, leading to a system warning and potentially a denial of service.

Statement

This flaw affects tracing buffer mmap usage with fork(). When MADVISE_DOFORK overrides VM_DONTCOPY, the user_mapped refcount isn't incremented for child VMAs, causing double-close on both processes exiting. This triggers a WARN_ON but doesn't cause memory corruption. Requires specific madvise() usage with tracing mmap.

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 Score3.35.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactLowHighN/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:N/I:N/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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