CVE-2026-98588

Description

A flaw was found in the Linux kernel's Berkeley Packet Filter (BPF) subsystem. When allocating a socket map with an excessively large entry count, a signed integer overflow occurs during cleanup when the map is released. A local user with permission to create BPF maps can trigger this issue to cause an out-of-bounds memory write, leading to kernel memory corruption or a Denial of Service (DoS) through a system crash.

Statement

This vulnerability is rated as Moderate impact for Red Hat Enterprise Linux because exploitation requires elevated administrative privileges to create BPF maps, as well as an extraordinarily large host memory allocation to trigger the condition. By default, unprivileged access to the eBPF subsystem is restricted on Red Hat platforms, preventing standard local users from instantiating socket maps. Even in environments where an attacker holds the necessary capabilities, inducing the bug requires exhausting tens of gigabytes of kernel memory to initiate the malformed cleanup, limiting the impact to kernel corruption or a denial of service.

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 Score4.1N/AN/A
Attack VectorLocalN/AN/A
Attack ComplexityHighN/AN/A
Privileges RequiredHighN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactNoneN/AN/A
Availability ImpactHighN/AN/A

Vector

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

Understanding the Weakness (CWE)

Integrity,Availability

Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart

Out of bounds memory access will very likely result in the corruption of relevant memory, and perhaps instructions, possibly leading to a crash.

Integrity,Confidentiality,Availability,Access Control,Other

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

If the corrupted memory can be effectively controlled, it may be possible to execute arbitrary code. If the corrupted memory is data rather than instructions, the system will continue to function with improper changes, possibly in violation of an implicit or explicit policy. The consequences would only be limited by how the affected data is used, such as an adjacent memory location that is used to specify whether the user has special privileges.

Access Control,Other

Technical Impact: Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Frequently Asked Questions

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