# CVE-2025-37833: net/niu: Niu requires MSIX ENTRY_DATA fields touch before entry reads

> A bug in the Linux kernel's niu network driver causes a fatal system trap on SPARC systems during initialization, leading to a denial of service.

- **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:** 8 May 2025
- **Updated:** 14 Sep 2026
- **Also known as:** BELL-CVE-2025-37833, DEBIAN-CVE-2025-37833, GHSA-3vhw-gffp-6qr6, ROOT-OS-DEBIAN-11-CVE-2025-37833, ROOT-OS-DEBIAN-12-CVE-2025-37833, ROOT-OS-UBUNTU-2204-CVE-2025-37833, ROOT-OS-UBUNTU-2404-CVE-2025-37833, UBUNTU-CVE-2025-37833

## What is CVE-2025-37833?

CVE-2025-37833 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 2025. 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:

net/niu: Niu requires MSIX ENTRY_DATA fields touch before entry reads

Fix niu_try_msix() to not cause a fatal trap on sparc systems.

Set PCI_DEV_FLAGS_MSIX_TOUCH_ENTRY_DATA_FIRST on the struct pci_dev to
work around a bug in the hardware or firmware.

For each vector entry in the msix table, niu chips will cause a fatal
trap if any registers in that entry are read before that entries'
ENTRY_DATA register is written to. Testing indicates writes to other
registers are not sufficient to prevent the fatal trap, however the value
does not appear to matter. This only needs to happen once after power up,
so simply rebooting into a kernel lacking this fix will NOT cause the
trap.

NON-RESUMABLE ERROR: Reporting on cpu 64
NON-RESUMABLE ERROR: TPC [0x00000000005f6900] <msix_prepare_msi_desc+0x90/0xa0>
NON-RESUMABLE ERROR: RAW [4010000000000016:00000e37f93e32ff:0000000202000080:ffffffffffffffff
NON-RESUMABLE ERROR:      0000000800000000:0000000000000000:0000000000000000:0000000000000000]
NON-RESUMABLE ERROR: handle [0x4010000000000016] stick [0x00000e37f93e32ff]
NON-RESUMABLE ERROR: type [precise nonresumable]
NON-RESUMABLE ERROR: attrs [0x02000080] < ASI sp-faulted priv >
NON-RESUMABLE ERROR: raddr [0xffffffffffffffff]
NON-RESUMABLE ERROR: insn effective address [0x000000c50020000c]
NON-RESUMABLE ERROR: size [0x8]
NON-RESUMABLE ERROR: asi [0x00]
CPU: 64 UID: 0 PID: 745 Comm: kworker/64:1 Not tainted 6.11.5 #63
Workqueue: events work_for_cpu_fn
TSTATE: 0000000011001602 TPC: 00000000005f6900 TNPC: 00000000005f6904 Y: 00000000    Not tainted
TPC: <msix_prepare_msi_desc+0x90/0xa0>
g0: 00000000000002e9 g1: 000000000000000c g2: 000000c50020000c g3: 0000000000000100
g4: ffff8000470307c0 g5: ffff800fec5be000 g6: ffff800047a08000 g7: 0000000000000000
o0: ffff800014feb000 o1: ffff800047a0b620 o2: 0000000000000011 o3: ffff800047a0b620
o4: 0000000000000080 o5: 0000000000000011 sp: ffff800047a0ad51 ret_pc: 00000000005f7128
RPC: <__pci_enable_msix_range+0x3cc/0x460>
l0: 000000000000000d l1: 000000000000c01f l2: ffff800014feb0a8 l3: 0000000000000020
l4: 000000000000c000 l5: 0000000000000001 l6: 0000000020000000 l7: ffff800047a0b734
i0: ffff800014feb000 i1: ffff800047a0b730 i2: 0000000000000001 i3: 000000000000000d
i4: 0000000000000000 i5: 0000000000000000 i6: ffff800047a0ae81 i7: 00000000101888b0
I7: <niu_try_msix.constprop.0+0xc0/0x130 [niu]>
Call Trace:
[<00000000101888b0>] niu_try_msix.constprop.0+0xc0/0x130 [niu]
[<000000001018f840>] niu_get_invariants+0x183c/0x207c [niu]
[<00000000101902fc>] niu_pci_init_one+0x27c/0x2fc [niu]
[<00000000005ef3e4>] local_pci_probe+0x28/0x74
[<0000000000469240>] work_for_cpu_fn+0x8/0x1c
[<000000000046b008>] process_scheduled_works+0x144/0x210
[<000000000046b518>] worker_thread+0x13c/0x1c0
[<00000000004710e0>] kthread+0xb8/0xc8
[<00000000004060c8>] ret_from_fork+0x1c/0x2c
[<0000000000000000>] 0x0
Kernel panic - not syncing: Non-resumable error.

## Which versions are affected by CVE-2025-37833?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-37833?

Apply the vendor's patch.

## Is CVE-2025-37833 being exploited?

There is no known exploitation of CVE-2025-37833 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-2025-37833 and fix it if it is affected.

What it is: CVE-2025-37833 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 2025. 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-2025-37833 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-2025-37833/ (Markdown: https://insights.sbomify.com/CVE-2025-37833/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-37833
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-37833
- OSV: https://osv.dev/vulnerability/CVE-2025-37833

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-37833/
Summaries are generated and may contain mistakes; the official description above is the record.