# CVE-2026-80998: net: bnxt: ring the doorbell when SW USO exits early

> A bug in the Linux kernel bnxt network driver can cause TX queue stalls, leading to denial of service.

- **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:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-80998, GHSA-853c-vx6w-q6cv, UBUNTU-CVE-2026-80998

## What is CVE-2026-80998?

CVE-2026-80998 is a high-severity denial of service vulnerability in Linux, published on 11 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:

net: bnxt: ring the doorbell when SW USO exits early

When a burst of packets is handed down to the driver, the driver defers
the doorbell to the end by setting txr->kick_pending = 1. The normal TX
path handles this, but the SW USO path can miss it if it returns
early.

If bnxt_sw_udp_gso_xmit runs but returns early with NETDEV_TX_BUSY and
txr->kick_pending was previously set to 1, then the TX queue can
stall because the driver wrote some BDs but never wrote the doorbell.
The device won't know to do the TX which would generate the completion
that would wake the queue back up.

Simplify bnxt_sw_udp_gso_xmit to set txr->kick_pending in its success
case and check the flag on return. The added check after
bnxt_sw_udp_gso_xmit returns ensures that any pending doorbells are
written handling both successful USO and any early returns, which
prevents the TX queue stall mentioned above.

This TX queue stall was observed on a production system with a netdev TX
watchdog informing about the queue stall.

## Which versions are affected by CVE-2026-80998?


## How do I fix CVE-2026-80998?

Apply the vendor's patch.

## Is CVE-2026-80998 being exploited?

There is no known exploitation of CVE-2026-80998 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80998 and fix it if it is affected.

What it is: CVE-2026-80998 is a high-severity denial of service vulnerability in Linux, published on 11 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-2026-80998 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-2026-80998/ (Markdown: https://insights.sbomify.com/CVE-2026-80998/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80998
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80998
- OSV: https://osv.dev/vulnerability/CVE-2026-80998

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80998/
Summaries are generated and may contain mistakes; the official description above is the record.