CVE-2026-47333 is a vulnerability in Ubuntu Linux kernels 6.8, 6.17, and 7.0 related to AppArmor SAUCE patches. The flaw causes incorrect computation of an internal buffer size, leading to a heap memory out-of-bounds read in the AppArmor notification handling code. This can be exploited by a local unprivileged user to cause kernel memory corruption and potentially affect the processing of AppArmor policies. The vulnerability is part of a set of Linux kernel security issues addressed in Ubuntu security notices USN-8370-1 and USN-8371-1. The vendor advisory confirms that patches fixing this issue are available and recommends updating to the specified fixed kernel package versions.

An unprivileged local attacker can trigger this vulnerability to cause out-of-bounds reads of kernel memory, leading to information disclosure and kernel memory corruption. This may affect the integrity and confidentiality of the system by influencing AppArmor policy processing. The CVSS score of 7.8 indicates a high impact on confidentiality, integrity, and availability. There are no known exploits in the wild at the time of publication.

A patch is available from Ubuntu to address this vulnerability. Users should update their systems to the fixed kernel package versions as listed in the Ubuntu security notices USN-8370-1 and USN-8371-1 and reboot the system to apply the changes. Due to an ABI change, recompilation and reinstallation of third-party kernel modules may be required. No additional mitigation actions are specified by the vendor.