# CVE-2026-80943: wifi: rtlwifi: rtl8192du: check QoS TID before indexing tids

> An out-of-bounds array access in the rtl8192du WiFi driver allows attackers to cause a denial of service via crafted QoS TID values.

- **Severity:** High 7.6 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H`)
- **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:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-80943, DEBIAN-CVE-2026-80943, GHSA-8f9m-rj4x-3w9p, UBUNTU-CVE-2026-80943

## What is CVE-2026-80943?

CVE-2026-80943 is a high-severity vulnerability in Linux, published on 11 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:

wifi: rtlwifi: rtl8192du: check QoS TID before indexing tids

rtl92du_tx_fill_desc() uses ieee80211_get_tid() to read the QoS TID
from the 802.11 header and then uses it as an index into
sta_entry->tids[]. ieee80211_get_tid() returns the low 4-bit QoS TID
value, so the result can be in the range 0..15.

rtlwifi only allocates MAX_TID_COUNT entries for sta_entry->tids[], and
MAX_TID_COUNT is 9. A QoS TID greater than 8 therefore indexes past the
aggregation state array. Keep the default RTL_AGG_STOP state for
out-of-range TIDs, matching rtl92cu_tx_fill_desc().

This issue was detected by our static analysis tool and confirmed by
manual audit. UBSAN validation for the same bug pattern reports an
array-index-out-of-bounds access with index 10 for type
'rtl_tid_data [9]'.

## Which versions are affected by CVE-2026-80943?


## How do I fix CVE-2026-80943?

Apply the vendor's patch.

## Is CVE-2026-80943 being exploited?

There is no known exploitation of CVE-2026-80943 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80943 and fix it if it is affected.

What it is: CVE-2026-80943 is a high-severity vulnerability in Linux, published on 11 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-2026-80943 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-2026-80943/ (Markdown: https://insights.sbomify.com/CVE-2026-80943/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80943
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80943
- OSV: https://osv.dev/vulnerability/CVE-2026-80943

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80943/
Summaries are generated and may contain mistakes; the official description above is the record.