CVE-2026-46254

CVE-2026-46254 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

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.

Frequently asked questions

What is CVE-2026-46254?
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.
How severe is CVE-2026-46254?
CVE-2026-46254 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-46254 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-46254?
CVE-2026-46254 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-46254?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-46254 have an EU (EUVD) identifier?
Yes. CVE-2026-46254 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34116.
When was CVE-2026-46254 published?
CVE-2026-46254 was published on 2026-06-03 and last updated on 2026-06-17.

References

Affected products (1)

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