# CVE-2026-98571: net: stmmac: clear stale buf->page after recycling on skb build failure

> A use-after-free vulnerability in the Linux kernel stmmac driver allows attackers to cause denial of service or potentially execute code via crafted network packets.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-98571, DEBIAN-CVE-2026-98571, GHSA-j482-jx6v-w2pf, UBUNTU-CVE-2026-98571

## What is CVE-2026-98571?

CVE-2026-98571 is an use after free vulnerability in Linux, published on 18 Oct 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:

net: stmmac: clear stale buf->page after recycling on skb build failure

In stmmac_rx(), when napi_build_skb() fails the descriptor page is
recycled back to the page pool with page_pool_recycle_direct(), but
buf->page is left pointing at the recycled page, unlike every other
consumption site in the function which clears the pointer after handing
the page away.

With the stale pointer stmmac_rx_refill() skips the replacement
allocation and programs the already-recycled page back into the RX
descriptor.

Clear buf->page on the napi_build_skb() failure path to keep the buffer
lifecycle consistent with the other consumption sites.

## Which versions are affected by CVE-2026-98571?


## How do I fix CVE-2026-98571?

Apply the vendor's patch.

## Is CVE-2026-98571 being exploited?

There is no known exploitation of CVE-2026-98571 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98571 and fix it if it is affected.

What it is: CVE-2026-98571 is an use after free vulnerability in Linux, published on 18 Oct 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-2026-98571 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-2026-98571/ (Markdown: https://insights.sbomify.com/CVE-2026-98571/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98571
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98571
- OSV: https://osv.dev/vulnerability/CVE-2026-98571

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98571/
Summaries are generated and may contain mistakes; the official description above is the record.