CVE-2026-47328

Invalid pointer deallocation in Ubuntu Linux AppArmor notification handling

Published May 28, 2026 CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed

Description

Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which incorrectly attempt to free a pointer which was not previously kmalloc()d, while at the same time leaking allocated memory. The bug can be triggered by an unprivileged local user and can result in the corruption of slab metadata and could lead to resource exhaustion.

Analysis

Technical impact

The vulnerability originates in the AppArmor SAUCE patches in Ubuntu Linux kernels 6.8, 6.17, and 7.0, where the code attempts to free a pointer that was not allocated by kmalloc. This incorrect deallocation corrupts slab metadata and leaks allocated memory, allowing an unprivileged local user to trigger the bug. The resulting memory corruption can cause resource exhaustion or further kernel instability.

Affected Systems

Affected systems are Canonical Ubuntu Linux systems running kernel version 6.8, 6.17, or 7.0. The issue exists in the AppArmor SAUCE patches applied to those kernel releases.

Risk and Exploitability

The CVSS score of 6.1 indicates a moderate severity. The EPSS score is not available, and the vulnerability is not listed in the CISA KEV catalog. The attack vector is local; an unprivileged user must execute code on the affected machine to trigger the bug. Exploitation could lead to kernel memory corruption and a denial‑of‑service by exhausting system resources, but the requirement for local access limits its threat scope to compromised or poorly managed systems.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Canonical

Ubuntu Linux

unaffected

Version	Status	Constraints
`6.8.0`	affected	< 6.8.0-124.124
`6.17.0`	affected	< 6.17.0-35.35
`7.0.0`	affected	< 7.0.0-22.22

Configuration 1 [-]

OR	cpe:2.3:o:canonical:ubuntu_linux:24.04:::::::*
	cpe:2.3:o:canonical:ubuntu_linux:25.10:::::::*
	cpe:2.3:o:canonical:ubuntu_linux:26.04:::::::*

No data.

Vendor Product Versions

Canonical

Ubuntu Linux

Version	Status	Scheme	Platform
`[6.8.0,6.8.0-124.124)`	affected	semver	—
`[6.17.0,6.17.0-35.35)`	affected	semver	—
`[7.0.0,7.0.0-22.22)`	affected	semver	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Upgrade the kernel to a patched release (e.g., 6.8.1 or later, 6.17.1 or later, or 7.0.1 or later) and reboot the system
Apply any available security updates that contain the AppArmor SAUCE patch from Canonical’s package repositories
If immediate kernel updates are unavailable, restrict local user privileges so they cannot trigger AppArmor notification handling (e.g., remove write or execute permissions for local policy files)
Monitor kernel logs for signs of slab corruption or OOM events and address anomalies promptly

Generated by OpenCVE AI on May 28, 2026 at 20:27 UTC.

Tracking

Advisories

Source	ID	Title
Ubuntu USN	USN-8370-1	Linux kernel vulnerabilities
Ubuntu USN	USN-8371-1	Linux kernel vulnerabilities
Ubuntu USN	USN-8373-1	Linux kernel vulnerabilities
Ubuntu USN	USN-8374-1	Linux kernel vulnerabilities
Ubuntu USN	USN-8440-1	Linux kernel (Azure) vulnerabilities
Ubuntu USN	USN-8489-1	Linux kernel (OEM) vulnerabilities
Ubuntu USN	USN-8497-1	Linux kernel (Low Latency) vulnerabilities
Ubuntu USN	USN-8499-1	Linux kernel (Xilinx) vulnerabilities
Ubuntu USN	USN-8569-1	Linux kernel (HWE) vulnerabilities
Ubuntu USN	USN-8393-1	Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN	USN-8461-1	Linux kernel (Azure) vulnerabilities

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.093% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/noble/commit/?id=7f3c4902c39432ce7ea0d384cb70eba282247fac

History

Jun 9, 2026 2:45 PM Affected versions updated View changes

Type	Values Removed	Values Added
CPEs		cpe:2.3:o:canonical:ubuntu_linux:24.04:::::::* cpe:2.3:o:canonical:ubuntu_linux:25.10:::::::* cpe:2.3:o:canonical:ubuntu_linux:26.04:::::::*

May 28, 2026 9:15 PM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Canonical Canonical ubuntu Linux
Vendors & Products		Canonical Canonical ubuntu Linux

May 28, 2026 8:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

May 28, 2026 7:00 PM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which incorrectly attempt to free a pointer which was not previously kmalloc()d, while at the same time leaking allocated memory. The bug can be triggered by an unprivileged local user and can result in the corruption of slab metadata and could lead to resource exhaustion.
Title		Invalid pointer deallocation in Ubuntu Linux AppArmor notification handling
Weaknesses		CWE-590
References		https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/noble/commit/?id=7f3c4902c39432ce7ea0d384cb70eba282247fac
Metrics		cvssV3_1 `{'score': 6.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H'}`