CVE-2026-43449 | nvme-pci: Fix slab-out-of-bounds in nvme_dbbuf_set

In the Linux kernel, the following vulnerability has been resolved: nvme-pci: Fix slab-out-of-bounds in nvme_dbbuf_set dev->online_queues is a count incremented in nvme_init_queue. Thus, valid indices are 0 through dev->online_queues − 1. This patch fixes the loop condition to ensure the index stays within the valid range. Index 0 is excluded because it is the admin queue. KASAN splat: ================================================================== BUG: KASAN: slab-out-of-bounds in nvme_dbbuf_free drivers/nvme/host/pci.c:377 [inline] BUG: KASAN: slab-out-of-bounds in nvme_dbbuf_set+0x39c/0x400 drivers/nvme/host/pci.c:404 Read of size 2 at addr ffff88800592a574 by task kworker/u8:5/74 CPU: 0 UID: 0 PID: 74 Comm: kworker/u8:5 Not tainted 6.19.0-dirty #10 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Workqueue: nvme-reset-wq nvme_reset_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xea/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xce/0x5d0 mm/kasan/report.c:482 kasan_report+0xdc/0x110 mm/kasan/report.c:595 __asan_report_load2_noabort+0x18/0x20 mm/kasan/report_generic.c:379 nvme_dbbuf_free drivers/nvme/host/pci.c:377 [inline] nvme_dbbuf_set+0x39c/0x400 drivers/nvme/host/pci.c:404 nvme_reset_work+0x36b/0x8c0 drivers/nvme/host/pci.c:3252 process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x65c/0xe60 kernel/workqueue.c:3421 kthread+0x41a/0x930 kernel/kthread.c:463 ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 </TASK> Allocated by task 34 on cpu 1 at 4.241550s: kasan_save_stack+0x2c/0x60 mm/kasan/common.c:57 kasan_save_track+0x1c/0x70 mm/kasan/common.c:78 kasan_save_alloc_info+0x3c/0x50 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xb5/0xc0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_node_noprof+0x2bf/0x8d0 mm/slub.c:5663 kmalloc_array_node_noprof include/linux/slab.h:1075 [inline] nvme_pci_alloc_dev drivers/nvme/host/pci.c:3479 [inline] nvme_probe+0x2f1/0x1820 drivers/nvme/host/pci.c:3534 local_pci_probe+0xef/0x1c0 drivers/pci/pci-driver.c:324 pci_call_probe drivers/pci/pci-driver.c:392 [inline] __pci_device_probe drivers/pci/pci-driver.c:417 [inline] pci_device_probe+0x743/0x920 drivers/pci/pci-driver.c:451 call_driver_probe drivers/base/dd.c:583 [inline] really_probe+0x29b/0xb70 drivers/base/dd.c:661 __driver_probe_device+0x3b0/0x4a0 drivers/base/dd.c:803 driver_probe_device+0x56/0x1f0 drivers/base/dd.c:833 __driver_attach_async_helper+0x155/0x340 drivers/base/dd.c:1159 async_run_entry_fn+0xa6/0x4b0 kernel/async.c:129 process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x65c/0xe60 kernel/workqueue.c:3421 kthread+0x41a/0x930 kernel/kthread.c:463 ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 The buggy address belongs to the object at ffff88800592a000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 244 bytes to the right of allocated 1152-byte region [ffff88800592a000, ffff88800592a480) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5928 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfffffc0000040(head|node=0|zone=1|lastcpupid=0x1fffff) page_type: f5(slab) raw: 000fffffc0000040 ffff888001042000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 000fffffc0000040 ffff888001042000 00000 ---truncated---

Published: 2026-05-08 Last update: 2026-05-21 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2026-43449 is rated Low Risk (30.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-43449

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-09 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-43449

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.1 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.2 [email protected]

Weakness enumeration for CVE-2026-43449

GitHub Security Advisory for CVE-2026-43449

GHSA-hv7m-w2x8-mf6q · Severity: high — In the Linux kernel, the following vulnerability has been resolved: nvme-pci: Fix slab-out-of...

OS Trackers for CVE-2026-43449

vendor priority summary link
debian not yet assigned CVE-2026-43449 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-43449
redhat medium https://access.redhat.com/security/cve/CVE-2026-43449
suse medium CVE-2026-43449 severity moderate: SUSE including 8 source package names (kernel-default, kernel-default-base, …), 36 product×package rows across 9 product lines (SUSE Linux Enterprise Micro 5.0, SUSE Linux Enterprise Micro 5.1, … (9 product lines)): Known Not Affected 36. https://www.suse.com/security/cve/CVE-2026-43449/
ubuntu medium CVE-2026-43449 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 170, needed 126, released 87, not-affected 17, needs-triage 1. https://ubuntu.com/security/CVE-2026-43449

Affected software / configurations for CVE-2026-43449

Vendor Product Version Raw CPE
linux linux_kernel >= 4.14.210, < 4.15 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.19.161, < 4.20 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.4.81, < 5.5 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.9.12, < 5.10 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.10.1, < 5.10.253 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.11, < 5.15.203 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.16, < 6.1.167 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.2, < 6.6.130 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.7, < 6.12.78 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.18.19 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.19, < 6.19.9 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 5.10 cpe:2.3:o:linux:linux_kernel:5.10:-:*:*:*:*:*:*
linux linux_kernel 5.10 cpe:2.3:o:linux:linux_kernel:5.10:rc5:*:*:*:*:*:*
linux linux_kernel 5.10 cpe:2.3:o:linux:linux_kernel:5.10:rc6:*:*:*:*:*:*
linux linux_kernel 5.10 cpe:2.3:o:linux:linux_kernel:5.10:rc7:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*

References for CVE-2026-43449

cvelogic Threat Intelligence