# CVE-2026-98544: bna: prevent IOC timer rearm during teardown

> A use-after-free vulnerability in the Linux kernel bna driver allows local attackers to cause denial of service or execute code during device teardown.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-108945, BELL-CVE-2026-98544, DEBIAN-CVE-2026-98544, GHSA-crgf-pp48-gvh7, UBUNTU-CVE-2026-98544

## What is CVE-2026-98544?

CVE-2026-98544 is an use after free vulnerability in Linux, published on 18 Oct 2026. 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:

bna: prevent IOC timer rearm during teardown

bna: prevent IOC timer rearm during teardown

bnad_pci_remove() and the probe disable_ioceth path call
timer_delete_sync() for ioc_timer, sem_timer and hb_timer, but not for
iocpf_timer.  bnad_iocpf_timeout() then takes bnad->bna_lock after
free_netdev() has freed the struct bnad.

Deleting iocpf_timer last does not fix this.  sem_timer and
iocpf_timer rearm each other: bnad_iocpf_sem_timeout() can arm
iocpf_timer, and bnad_iocpf_timeout() arms sem_timer from
bfa_ioc_hw_sem_get() when the semaphore is busy.
timer_delete_sync() only waits out its own callback.
bnad_ioceth_disable() can time out and leave that callback live.

Shut all four IOC timers down with timer_shutdown_sync() on both
paths, so a later mod_timer() is ignored.

This issue was identified during our ongoing static-analysis research
while reviewing kernel code.

## Which versions are affected by CVE-2026-98544?


## How do I fix CVE-2026-98544?

Apply the vendor's patch.

## Is CVE-2026-98544 being exploited?

There is no known exploitation of CVE-2026-98544 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98544 and fix it if it is affected.

What it is: CVE-2026-98544 is an use after free vulnerability in Linux, published on 18 Oct 2026. 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-2026-98544 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-2026-98544/ (Markdown: https://insights.sbomify.com/CVE-2026-98544/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98544
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98544
- OSV: https://osv.dev/vulnerability/CVE-2026-98544

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98544/
Summaries are generated and may contain mistakes; the official description above is the record.