CVE-2026-46254
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
In the Linux kernel, the AppArmor module has a vulnerability where DFA (Deterministic Finite Automaton) tables from kernel or userspace are not guaranteed to be 8-byte aligned, causing unaligned memory accesses on various architectures. This triggers warnings and potential kernel panics.
Risk Assessment
The risk involves possible kernel panic or unpredictable system behavior when loading AppArmor profiles, potentially leading to service disruption or system crash.
Recommendation
Immediately update the Linux kernel to a version containing the fix that uses get_unaligned_xx() helpers to handle unaligned DFA tables. Monitor official security advisories from your Linux distribution.
Other vulnerabilities in Linux kernel
See all- CVE-2026-14367Low
A vulnerability in the I3C IBI subsystem of the Linux kernel (drivers/i3c/i3c_ibi_workq.c) stems from missing synchronization on the free-list of work nodes (sys_slist_t). Allocation and deallocation helpers are called from interrupt context (ISR) and the workqueue thread without locks, leading to a race condition. An attacker with physical access to the I3C bus can trigger a series of interrupts, causing list corruption, double allocation, or out-of-bounds writes.
- CVE-2026-80577Unknown
In the Linux kernel's drm/panthor driver, panthor_fw_load_section_entry() skips BO creation for zero-sized firmware sections but adds them to the section list, leading to NULL pointer dereference in later paths. The fix skips adding such sections to the list.
- CVE-2026-80571Unknown
In the Linux kernel powerpc/pseries papr-phy-attest, missing validation of cmd.length could lead to buffer overflow. The fix adds length checks and fixes memory leaks on error paths.
- CVE-2026-80567Unknown
In the Linux kernel Synaptics RMI4 driver (F54), worker errors were not propagated to the V4L2 queue, causing stale or uninitialized data to be delivered to userspace. The fix adds error checking and marks buffers as error state.
- CVE-2026-80566Unknown
In the Linux kernel, the hynitron_cstxxx driver improperly validated touch count and finger IDs. This can lead to corrupted touch state or out-of-bounds buffer access.
- CVE-2026-80564Unknown
In the Linux kernel, the gve driver lacks an implementation of adjfine, leading to a NULL pointer dereference when triggered from userspace, e.g., via testptp.
- CVE-2026-80563Unknown
A use-after-free vulnerability was found in the Linux kernel's gpio-sloppy-logic-analyzer driver. The 'trigger' debugfs file lacked proper protection, allowing a write to freed memory during device unbind. The issue was fixed by using debugfs_create_file() instead of debugfs_create_file_unsafe().
- CVE-2026-80543Unknown
In the Linux kernel, the xcrb_msg_to_type6cprb_msgx() and xcrb_msg_to_type6_ep11cprb_msgx() functions for s390/zcrypt copy a user space message into a kernel buffer based on length, but further processing assumes 4-byte alignment. As a result, up to 3 bytes of uninitialized kernel memory are forwarded to further processing, potentially exposing kernel memory to the crypto card firmware.
- CVE-2026-80542Unknown
In the Linux kernel, the amdgpu driver for AMD Display has a NULL pointer dereference in amdgpu_dm_crtc_set_vblank() when vblank is enabled or queried before a stream is attached to acrtc_state->stream. This can lead to a system crash.
- CVE-2026-80535Unknown
In the Linux kernel XFS filesystem, during directory tree repair, a self-referential directory may be detected. In such a case, the repair code attempts to lock the same inode twice (double iolock/ilock), leading to a deadlock. The fix detects this corner case and handles it appropriately.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: AppArmor: Allow apparmor to handle unaligned dfa tables The dfa tables can originate from kernel or userspace and 8-byte alignment isn't always guaranteed and as such may trigger unaligned memory accesses on various architectures. Resulting in the following [ 73.901376] WARNING: CPU: 0 PID: 341 at security/apparmor/match.c:316 aa_dfa_unpack+0x6cc/0x720 [ 74.015867] Modules linked in: binfmt_misc evdev flash sg drm drm_panel_orientation_quirks backlight i2c_core configfs nfnetlink autofs4 ext4 crc16 mbcache jbd2 hid_generic usbhid sr_mod hid cdrom sd_mod ata_generic ohci_pci ehci_pci ehci_hcd ohci_hcd pata_ali libata sym53c8xx scsi_transport_spi tg3 scsi_mod usbcore libphy scsi_common mdio_bus usb_common [ 74.428977] CPU: 0 UID: 0 PID: 341 Comm: apparmor_parser Not tainted 6.18.0-rc6+ #9 NONE [ 74.536543] Call Trace: [ 74.568561] [<0000000000434c24>] dump_stack+0x8/0x18 [ 74.633757] [<0000000000476438>] __warn+0xd8/0x100 [ 74.696664] [<00000000004296d4>] warn_slowpath_fmt+0x34/0x74 [ 74.771006] [<00000000008db28c>] aa_dfa_unpack+0x6cc/0x720 [ 74.843062] [<00000000008e643c>] unpack_pdb+0xbc/0x7e0 [ 74.910545] [<00000000008e7740>] unpack_profile+0xbe0/0x1300 [ 74.984888] [<00000000008e82e0>] aa_unpack+0xe0/0x6a0 [ 75.051226] [<00000000008e3ec4>] aa_replace_profiles+0x64/0x1160 [ 75.130144] [<00000000008d4d90>] policy_update+0xf0/0x280 [ 75.201057] [<00000000008d4fc8>] profile_replace+0xa8/0x100 [ 75.274258] [<0000000000766bd0>] vfs_write+0x90/0x420 [ 75.340594] [<00000000007670cc>] ksys_write+0x4c/0xe0 [ 75.406932] [<0000000000767174>] sys_write+0x14/0x40 [ 75.472126] [<0000000000406174>] linux_sparc_syscall+0x34/0x44 [ 75.548802] ---[ end trace 0000000000000000 ]--- [ 75.609503] dfa blob stream 0xfff0000008926b96 not aligned. [ 75.682695] Kernel unaligned access at TPC[8db2a8] aa_dfa_unpack+0x6e8/0x720 Work around it by using the get_unaligned_xx() helpers.

