CVE-2026-47332 affects Ubuntu Linux kernel versions 6.8, 6.17, and 7.0 with AppArmor SAUCE patches that incorrectly validate the size of an internal structure, leading to an out-of-bounds read in the notification handling code. This vulnerability allows an unprivileged local attacker to cause information disclosure from adjacent kernel memory objects. The issue is one among several Linux kernel vulnerabilities fixed in Ubuntu security notices USN-8370-1 and USN-8371-1, which address multiple flaws including memory leaks, NULL pointer dereferences, invalid frees, insufficient validation, uninitialized variables, and lock handling errors in AppArmor notification processing. The vendor advisory confirms that patches are available and recommends updating to fixed kernel package versions and rebooting the system.

An unprivileged local attacker can exploit this vulnerability to read out-of-bounds kernel memory, potentially disclosing sensitive information from adjacent slab objects. The vulnerability does not directly allow code execution or privilege escalation but can aid attackers in gathering information about the kernel memory layout or data. This issue is part of a broader set of kernel flaws that collectively could lead to privilege escalation, information disclosure, resource exhaustion, kernel crashes, or denial of service.

A patch is available from Ubuntu as detailed in security notices USN-8370-1 and USN-8371-1. Users should update their Linux kernel packages to the fixed versions provided for Ubuntu releases 6.8, 6.17, 7.0, and others as applicable, and reboot their systems to apply the updates. Due to an ABI change, recompilation and reinstallation of third-party kernel modules may be necessary. No additional mitigation steps are required beyond applying the official fixes.