CVE-2026-72458

A flaw was found in the Linux kernel's Apparmor security module. This vulnerability occurs in the unpack_pdb function, where it does not correctly handle a null pointer if a preceding operation, unpack_dfa, fails. This oversight can lead to a NULL pointer dereference, which typically results in a system crash and a Denial of Service (DoS) for the affected system.

A NULL pointer dereference flaw was found in the Linux kernel's AppArmor security module. In the unpack_pdb function in security/apparmor/policy_unpack.c, the pdb->dfa pointer is not checked for NULL after the preceding unpack_dfa operation fails, so a subsequently loaded malformed AppArmor policy can trigger a NULL pointer dereference that crashes the kernel, resulting in a local denial of service. Red Hat rated this flaw Moderate impact because exploitation requires local access with sufficient privileges to load a crafted AppArmor policy, and only system availability is affected (CVSS 3.1: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). The vulnerable code was introduced in upstream kernel version 6.17, after the kernel versions shipped in Red Hat's products, so all Red Hat Enterprise Linux (kernel, kernel-rt) and Red Hat In-Vehicle OS (kernel, kernel-ivos-qualcomm) components are marked NOT AFFECTED because the vulnerable code is not present in the shipped kernels.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.