# CVE-2024-26891: iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected

> A local attacker can trigger a system hang by disconnecting a PCIe device, causing the kernel to enter a deadly loop during IOMMU invalidation.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Apr 2024
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2024-26891, DEBIAN-CVE-2024-26891, GHSA-vmhf-rfw6-gg6x, UBUNTU-CVE-2024-26891

## What is CVE-2024-26891?

CVE-2024-26891 is a medium-severity denial of service vulnerability in Linux kernel, published on 17 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected

For those endpoint devices connect to system via hotplug capable ports,
users could request a hot reset to the device by flapping device's link
through setting the slot's link control register, as pciehp_ist() DLLSC
interrupt sequence response, pciehp will unload the device driver and
then power it off. thus cause an IOMMU device-TLB invalidation (Intel
VT-d spec, or ATS Invalidation in PCIe spec r6.1) request for non-existence
target device to be sent and deadly loop to retry that request after ITE
fault triggered in interrupt context.

That would cause following continuous hard lockup warning and system hang

[ 4211.433662] pcieport 0000:17:01.0: pciehp: Slot(108): Link Down
[ 4211.433664] pcieport 0000:17:01.0: pciehp: Slot(108): Card not present
[ 4223.822591] NMI watchdog: Watchdog detected hard LOCKUP on cpu 144
[ 4223.822622] CPU: 144 PID: 1422 Comm: irq/57-pciehp Kdump: loaded Tainted: G S
         OE    kernel version xxxx
[ 4223.822623] Hardware name: vendorname xxxx 666-106,
BIOS 01.01.02.03.01 05/15/2023
[ 4223.822623] RIP: 0010:qi_submit_sync+0x2c0/0x490
[ 4223.822624] Code: 48 be 00 00 00 00 00 08 00 00 49 85 74 24 20 0f 95 c1 48 8b
 57 10 83 c1 04 83 3c 1a 03 0f 84 a2 01 00 00 49 8b 04 24 8b 70 34 <40> f6 c6 1
0 74 17 49 8b 04 24 8b 80 80 00 00 00 89 c2 d3 fa 41 39
[ 4223.822624] RSP: 0018:ffffc4f074f0bbb8 EFLAGS: 00000093
[ 4223.822625] RAX: ffffc4f040059000 RBX: 0000000000000014 RCX: 0000000000000005
[ 4223.822625] RDX: ffff9f3841315800 RSI: 0000000000000000 RDI: ffff9f38401a8340
[ 4223.822625] RBP: ffff9f38401a8340 R08: ffffc4f074f0bc00 R09: 0000000000000000
[ 4223.822626] R10: 0000000000000010 R11: 0000000000000018 R12: ffff9f384005e200
[ 4223.822626] R13: 0000000000000004 R14: 0000000000000046 R15: 0000000000000004
[ 4223.822626] FS:  0000000000000000(0000) GS:ffffa237ae400000(0000)
knlGS:0000000000000000
[ 4223.822627] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4223.822627] CR2: 00007ffe86515d80 CR3: 000002fd3000a001 CR4: 0000000000770ee0
[ 4223.822627] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 4223.822628] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 4223.822628] PKRU: 55555554
[ 4223.822628] Call Trace:
[ 4223.822628]  qi_flush_dev_iotlb+0xb1/0xd0
[ 4223.822628]  __dmar_remove_one_dev_info+0x224/0x250
[ 4223.822629]  dmar_remove_one_dev_info+0x3e/0x50
[ 4223.822629]  intel_iommu_release_device+0x1f/0x30
[ 4223.822629]  iommu_release_device+0x33/0x60
[ 4223.822629]  iommu_bus_notifier+0x7f/0x90
[ 4223.822630]  blocking_notifier_call_chain+0x60/0x90
[ 4223.822630]  device_del+0x2e5/0x420
[ 4223.822630]  pci_remove_bus_device+0x70/0x110
[ 4223.822630]  pciehp_unconfigure_device+0x7c/0x130
[ 4223.822631]  pciehp_disable_slot+0x6b/0x100
[ 4223.822631]  pciehp_handle_presence_or_link_change+0xd8/0x320
[ 4223.822631]  pciehp_ist+0x176/0x180
[ 4223.822631]  ? irq_finalize_oneshot.part.50+0x110/0x110
[ 4223.822632]  irq_thread_fn+0x19/0x50
[ 4223.822632]  irq_thread+0x104/0x190
[ 4223.822632]  ? irq_forced_thread_fn+0x90/0x90
[ 4223.822632]  ? irq_thread_check_affinity+0xe0/0xe0
[ 4223.822633]  kthread+0x114/0x130
[ 4223.822633]  ? __kthread_cancel_work+0x40/0x40
[ 4223.822633]  ret_from_fork+0x1f/0x30
[ 4223.822633] Kernel panic - not syncing: Hard LOCKUP
[ 4223.822634] CPU: 144 PID: 1422 Comm: irq/57-pciehp Kdump: loaded Tainted: G S
         OE     kernel version xxxx
[ 4223.822634] Hardware name: vendorname xxxx 666-106,
BIOS 01.01.02.03.01 05/15/2023
[ 4223.822634] Call Trace:
[ 4223.822634]  <NMI>
[ 4223.822635]  dump_stack+0x6d/0x88
[ 4223.822635]  panic+0x101/0x2d0
[ 4223.822635]  ? ret_from_fork+0x11/0x30
[ 4223.822635]  nmi_panic.cold.14+0xc/0xc
[ 4223.822636]  watchdog_overflow_callback.cold.8+0x6d/0x81
[ 4223.822636]  __perf_event_overflow+0x4f/0xf0
[ 4223.822636]  handle_pmi_common
---truncated---

## Which versions are affected by CVE-2024-26891?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-26891?

Apply the vendor's patch.

## Is CVE-2024-26891 being exploited?

There is no known exploitation of CVE-2024-26891 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-26891 and fix it if it is affected.

What it is: CVE-2024-26891 is a medium-severity denial of service vulnerability in Linux kernel, published on 17 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-26891 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-26891/ (Markdown: https://insights.sbomify.com/CVE-2024-26891/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-26891
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-26891
- OSV: https://osv.dev/vulnerability/CVE-2024-26891

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-26891/
Summaries are generated and may contain mistakes; the official description above is the record.