Linux KernelOperating system · Linux

CVE-2026-46055

HIGH · 7.1 CVSS v3.1 Published 2026-05-27
Fix available
A fix is available. Upgrade to 7.0.4 or later.
See remediation →
73/100
Remediation priority · Elevated
Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: apparmor: Fix string overrun due to missing termination When booting Ubuntu 26.04 with Linux 7.0-rc4 on an ARM64 Qualcomm Snapdragon X1 we see a string buffer overrun: BUG: KASAN: slab-out-of-bounds in aa_dfa_match (security/apparmor/match.c:535) Read of size 1 at addr ffff0008901cc000 by task snap-update-ns/2120 CPU: 5 UID: 60578 PID: 2120 Comm: snap-update-ns Not tainted 7.0.0-rc4+ #22 PREEMPTLAZY Hardware name: LENOVO 83ED/LNVNB161216, BIOS NHCN60WW 09/11/2025 Call trace: show_stack (arch/arm64/kernel/stacktrace.c:501) (C) dump_stack_lvl (lib/dump_stack.c:122) print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) kasan_report (mm/kasan/report.c:597) __asan_report_load1_noabort (mm/kasan/report_generic.c:378) aa_dfa_match (security/apparmor/match.c:535) match_mnt_path_str (security/apparmor/mount.c:244 security/apparmor/mount.c:336) match_mnt (security/apparmor/mount.c:371) aa_bind_mount (security/apparmor/mount.c:447 (discriminator 4)) apparmor_sb_mount (security/apparmor/lsm.c:719 (discriminator 1)) security_sb_mount (security/security.c:1062 (discriminator 31)) path_mount (fs/namespace.c:4101) __arm64_sys_mount (fs/namespace.c:4172 fs/namespace.c:4361 fs/namespace.c:4338 fs/namespace.c:4338) invoke_syscall.constprop.0 (arch/arm64/kernel/syscall.c:35 arch/arm64/kernel/syscall.c:49) el0_svc_common.constprop.0 (./include/linux/thread_info.h:142 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2)) do_el0_svc (arch/arm64/kernel/syscall.c:152) el0_svc (arch/arm64/kernel/entry-common.c:80 arch/arm64/kernel/entry-common.c:725) el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:744) el0t_64_sync (arch/arm64/kernel/entry.S:596) Allocated by task 2120: kasan_save_stack (mm/kasan/common.c:58) kasan_save_track (./arch/arm64/include/asm/current.h:19 mm/kasan/common.c:70 mm/kasan/common.c:79) kasan_save_alloc_info (mm/kasan/generic.c:571) __kasan_kmalloc (mm/kasan/common.c:419) __kmalloc_noprof (./include/linux/kasan.h:263 mm/slub.c:5260 mm/slub.c:5272) aa_get_buffer (security/apparmor/lsm.c:2201) aa_bind_mount (security/apparmor/mount.c:442) apparmor_sb_mount (security/apparmor/lsm.c:719 (discriminator 1)) security_sb_mount (security/security.c:1062 (discriminator 31)) path_mount (fs/namespace.c:4101) __arm64_sys_mount (fs/namespace.c:4172 fs/namespace.c:4361 fs/namespace.c:4338 fs/namespace.c:4338) invoke_syscall.constprop.0 (arch/arm64/kernel/syscall.c:35 arch/arm64/kernel/syscall.c:49) el0_svc_common.constprop.0 (./include/linux/thread_info.h:142 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2)) do_el0_svc (arch/arm64/kernel/syscall.c:152) el0_svc (arch/arm64/kernel/entry-common.c:80 arch/arm64/kernel/entry-common.c:725) el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:744) el0t_64_sync (arch/arm64/kernel/entry.S:596) The buggy address belongs to the object at ffff0008901ca000 which belongs to the cache kmalloc-rnd-06-8k of size 8192 The buggy address is located 0 bytes to the right of allocated 8192-byte region [ffff0008901ca000, ffff0008901cc000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9101c8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:-1 pincount:0 flags: 0x8000000000000040(head|zone=2) page_type: f5(slab) raw: 8000000000000040 ffff000800016c40 fffffdffe2d14e10 ffff000800015c70 raw: 0000000000000000 0000000800010001 00000000f5000000 0000000000000000 head: 8000000000000040 ffff000800016c40 fffffdffe2d14e10 ffff000800015c70 head: 0000000000000000 0000000800010001 00000000f5000000 0000000000000000 head: 8000000000000003 fffffdffe2407201 fffffdffffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0008901cbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0008 ---truncated---

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 7.0, < 7.0.4

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 7.0.4 or later
Fixed in 7.0.4
Vendor patch git.kernel.org →
Recommended fix High confidence

Linux Kernel 7.0.4 or later

  1. Update the Linux kernel to version 7.0.4 or later using the system's package manager (e.g., apt-get update && apt-get install linux-image-<version>, or yum/dnf update kernel)
  2. After the kernel update, reboot the system to load the fixed kernel
  3. Verify the running kernel version with 'uname -r' to confirm the update was successful
Caveat Kernel upgrades may require rebuilding third-party kernel modules; ensure compatibility with the new kernel version before production deployment

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

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