# CVE-2026-98210: mmc: mxcmmc: cancel data work and watchdog on remove

> A use-after-free vulnerability in the Linux kernel mxcmmc driver allows local attackers to cause a denial of service or potentially execute code via race conditions during device removal.

- **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:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-106245, BELL-CVE-2026-98210, DEBIAN-CVE-2026-98210, GHSA-3899-r8v9-5w9h, UBUNTU-CVE-2026-98210

## What is CVE-2026-98210?

CVE-2026-98210 is an use after free vulnerability in Linux, published on 6 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:

mmc: mxcmmc: cancel data work and watchdog on remove

mxcmci_remove() frees the host through the devm tail, but neither it nor
mmc_remove_host() drains the driver's own asynchronous state.
host->watchdog, a 10 s timer armed on the DMA path in mxcmci_setup_data(),
is deleted only by the DMA- and IRQ-complete paths, which the remove path
does not explicitly drain; it can therefore fire after the host is freed
and dereference it in mxcmci_watchdog().  host->datawork, armed from the
IRQ handler on the PIO path, is not cancelled by the remove path either.

Free the devm-registered IRQ, then cancel datawork and delete the watchdog
in mxcmci_remove(), before dma_release_channel().  Freeing the IRQ first
keeps a trailing handler from re-arming datawork between the cancel and
the host free.  Both callbacks are non-self-rearming.

This issue was found by an in-house static analysis tool.

## Which versions are affected by CVE-2026-98210?


## How do I fix CVE-2026-98210?

Apply the vendor's patch.

## Is CVE-2026-98210 being exploited?

There is no known exploitation of CVE-2026-98210 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98210 and fix it if it is affected.

What it is: CVE-2026-98210 is an use after free vulnerability in Linux, published on 6 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-2026-98210 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-2026-98210/ (Markdown: https://insights.sbomify.com/CVE-2026-98210/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98210
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98210
- OSV: https://osv.dev/vulnerability/CVE-2026-98210

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98210/
Summaries are generated and may contain mistakes; the official description above is the record.