CVE-2026-98987

Description

A flaw was found in the Linux kernel's mount namespace subsystem. A local user with mount privileges can trigger this issue during recursive mount operations when the topmost mount in a chain is a mount namespace file. Because the kernel fails to inspect the topmost mount in the chain, propagated mount copies are incorrectly attached to inaccessible internal locations. This improper attachment can result in a Denial of Service (DoS) by rendering filesystems inaccessible and preventing them from being cleanly unmounted.

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 Score2.3N/AN/A
Attack VectorLocalN/AN/A
Attack ComplexityLowN/AN/A
Privileges RequiredHighN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactNoneN/AN/A
Availability ImpactLowN/AN/A

Vector

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

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability

This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.

Integrity

Technical Impact: Modify Memory

If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.

Confidentiality,Availability,Access Control

Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism

This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.

Frequently Asked Questions

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