# CVE-2026-97966: octeontx2-pf: reset HTB scheduler topology before freeing queues

> A flaw in the Linux kernel octeontx2-pf driver allows stale scheduler topology settings to persist, potentially affecting network traffic scheduling for other users.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-104250, BELL-CVE-2026-97966, DEBIAN-CVE-2026-97966, GHSA-m5mf-8q2j-8cgp, UBUNTU-CVE-2026-97966

## What is CVE-2026-97966?

CVE-2026-97966 is a vulnerability in Linux, published on 25 Sep 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:

octeontx2-pf: reset HTB scheduler topology before freeing queues

HTB offload programs NIX_AF_TLxX_TOPOLOGY on QoS-allocated scheduler
queues via otx2_qos_txschq_set_parent_topology(), but teardown freed
those queues without clearing TOPOLOGY.  The AF only restores PARENT and
SCHEDULE on free, so PRIO_ANCHOR/RR_PRIO settings can survive in the
shared scheduler pool and affect later allocations.

Add otx2_qos_reset_schq_topology() and otx2_qos_free_hw_schq() to zero
TL4 through TL2 TOPOLOGY before each schq is returned to the AF during
hierarchy teardown and cfg rollback.  Skip the aggregation level (TL1):
it is a per-tx-link queue shared by the PF, default Tx hierarchy and VFs,
and is not freed back to the AF by nix_txschq_free_one().

## Which versions are affected by CVE-2026-97966?


## How do I fix CVE-2026-97966?

Apply the vendor's patch.

## Is CVE-2026-97966 being exploited?

There is no known exploitation of CVE-2026-97966 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-97966 and fix it if it is affected.

What it is: CVE-2026-97966 is a vulnerability in Linux, published on 25 Sep 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-2026-97966 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-2026-97966/ (Markdown: https://insights.sbomify.com/CVE-2026-97966/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-97966
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-97966
- OSV: https://osv.dev/vulnerability/CVE-2026-97966

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-97966/
Summaries are generated and may contain mistakes; the official description above is the record.