# CVE-2026-98056: nvme: remove stale namespaces by NSID range during scan

> A malicious NVMe target can cause a kernel soft lockup and denial of service by reporting sparse namespace IDs, forcing excessive CPU usage during scanning.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-104754, BELL-CVE-2026-98056, DEBIAN-CVE-2026-98056, GHSA-q2jc-ghv3-8x67, UBUNTU-CVE-2026-98056

## What is CVE-2026-98056?

CVE-2026-98056 is a high-severity denial of service vulnerability in Linux, published on 25 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

nvme: remove stale namespaces by NSID range during scan

nvme_scan_ns_list() drops the stale namespaces in each gap in the
reported NSID list one NSID at a time. Every iteration calls
nvme_find_get_ns() to look the namespace up and removes it if it is
present. The loop runs once per NSID in the gap rather than once per
namespace actually present.

NSIDs are 32-bit, so a target with a sparse NSID space can make a
single gap spin the loop billions of times with nothing to remove.

  watchdog: BUG: soft lockup - CPU#4 stuck for 26s!
  Workqueue: nvme-wq nvme_scan_work [nvme_core]
  RIP: 0010:__srcu_read_unlock+0xb/0x20
  Call Trace:
   nvme_find_get_ns+0x7d/0xb0 [nvme_core]
   nvme_scan_ns_list+0xe8/0x280 [nvme_core]
   nvme_scan_work+0x18a/0x280 [nvme_core]
   process_one_work+0x197/0x380
   worker_thread+0x2fe/0x410
   kthread+0xe0/0x100

Rename nvme_remove_invalid_namespaces() to nvme_remove_nsid_range()
and give it an open (start, end) NSID range. ctrl->namespaces is
sorted by NSID, so the whole gap is dropped in a single walk that
stops once end is reached. This bounds the work by the namespaces
that are present instead of by the size of the gap.

## Which versions are affected by CVE-2026-98056?


## How do I fix CVE-2026-98056?

Apply the vendor's patch.

## Is CVE-2026-98056 being exploited?

There is no known exploitation of CVE-2026-98056 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98056 and fix it if it is affected.

What it is: CVE-2026-98056 is a high-severity denial of service vulnerability in Linux, published on 25 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98056 in the wild and no public exploit code.

Affected product: Linux. 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-2026-98056/ (Markdown: https://insights.sbomify.com/CVE-2026-98056/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98056
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98056
- OSV: https://osv.dev/vulnerability/CVE-2026-98056

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98056/
Summaries are generated and may contain mistakes; the official description above is the record.