CVE-2026-23268

Published Mar 18, 2026

Last updated 4 months ago

CVSS high 7.8
Ubuntu

Overview

AI description

Automated description summarized from trusted sources.

CVE-2026-23268 describes a vulnerability within the AppArmor component of the Linux kernel. This flaw allows an unprivileged local user to engage in a "confused deputy attack" by manipulating a privileged process. Through this manipulation, the unprivileged user can cause the privileged process to write to AppArmor interfaces. This access enables the unprivileged user to perform full policy management, including the ability to load, replace, and remove AppArmor security profiles. The consequences of such an action can involve bypassing user namespace restrictions, removing existing security confinements, and potentially leading to a Denial of Service (DoS) by preventing application execution.

Description
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix unprivileged local user can do privileged policy management An unprivileged local user can load, replace, and remove profiles by opening the apparmorfs interfaces, via a confused deputy attack, by passing the opened fd to a privileged process, and getting the privileged process to write to the interface. This does require a privileged target that can be manipulated to do the write for the unprivileged process, but once such access is achieved full policy management is possible and all the possible implications that implies: removing confinement, DoS of system or target applications by denying all execution, by-passing the unprivileged user namespace restriction, to exploiting kernel bugs for a local privilege escalation. The policy management interface can not have its permissions simply changed from 0666 to 0600 because non-root processes need to be able to load policy to different policy namespaces. Instead ensure the task writing the interface has privileges that are a subset of the task that opened the interface. This is already done via policy for confined processes, but unconfined can delegate access to the opened fd, by-passing the usual policy check.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

  1. lpe-toolkit has been updated with new LPE exploits! New exploits added: - RefluXFS CVE-2026-64600 - CrackArmor CVE-2026-23268 - skb_shift CVE-2026-43503 - GRO Flag Loss CVE-2026-43503 - snap-confine CVE-2026-8933 https://t.co/Uafh1WjbqV

    @portbuster1337

    23 Sept 2026

    6594 Impressions

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  2. Stop chasing CVEs. Start mastering Linux security. The latest kernel bugs (CVE-2025-40309 + CVE-2026-23268) exploit the SAME patterns from 5 years ago. Read more -> https://t.co/GZxDwbKmwW #SUSE https://t.co/f0phFKg9WA

    @Cezar_H_Linux

    20 Apr 2026

    129 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.