CVE-2026-23278

Description

A flaw was found in the Linux kernel's netfilter subsystem, specifically within the nf_tables component. This vulnerability occurs during transaction processing when the system incorrectly handles multiple pending catchall elements, particularly when the associated map is being removed. This can lead to a kernel warning and system instability, potentially causing a Denial of Service (DoS) for the affected system.

Statement

nf_tables transaction processing can involve more than one catchall element at the same time such as one live element and one pending element from a new batch. When a map that holds catchall elements is being removed the code must toggle all catchall elements. The prior logic stopped after the first viable candidate which could leave additional pending catchall elements in an inconsistent state and later trigger a warning in nft_data_release during abort cleanup. The issue is not directly network reachable and it is triggered by control plane configuration changes rather than packet traffic. Impact is primarily denial of service in environments that treat WARN as fatal or that cannot tolerate repeated abort warnings.

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)

Other,Confidentiality,Integrity

Technical Impact: Other; Read Application Data; Modify Application Data; DoS: Resource Consumption (Other)

It is possible to overflow the number of temporary files because directories typically have limits on the number of files allowed. This could create a denial of service problem.

Frequently Asked Questions

Want to get errata notifications? Sign up here.