# CVE-2026-98238: net: wwan: t7xx: validate the netif index in t7xx_ccmni_recv_skb()

> A missing bounds check in the Linux kernel t7xx WWAN driver allows out-of-bounds reads and potential code execution via crafted network packets.

- **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-106206, BELL-CVE-2026-98238, DEBIAN-CVE-2026-98238, GHSA-wwj9-jxr5-39jp, UBUNTU-CVE-2026-98238

## What is CVE-2026-98238?

CVE-2026-98238 is a memory corruption 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:

net: wwan: t7xx: validate the netif index in t7xx_ccmni_recv_skb()

The netif index carried in the DPMAIF PIT header is five bits wide,
but ccmni_inst[] only has room for NIC_DEV_MAX (21) entries.
t7xx_ccmni_recv_skb() indexes the array without a bounds check, so
indexes 21 to 31 read past it.  The out-of-bounds value lands in the
callback table that follows the array, which is never NULL, so the
existing !ccmni check does not catch it and the driver dereferences
whatever sits there as a struct t7xx_ccmni.

Drop the skb when the index is out of range.

Verified in a QEMU guest with a fault injector setting the netif
index to 25: the unpatched driver reads a value past ccmni_inst[],
which lands in the callback table, and dereferences it far enough to
queue the skb.  With this check the packet is dropped.  Well-formed
traffic on index 0 is unaffected.

Changes in v2: none.

## Which versions are affected by CVE-2026-98238?


## How do I fix CVE-2026-98238?

Apply the vendor's patch.

## Is CVE-2026-98238 being exploited?

There is no known exploitation of CVE-2026-98238 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98238 and fix it if it is affected.

What it is: CVE-2026-98238 is a memory corruption 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-2026-98238 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-2026-98238/ (Markdown: https://insights.sbomify.com/CVE-2026-98238/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98238
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98238
- OSV: https://osv.dev/vulnerability/CVE-2026-98238

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98238/
Summaries are generated and may contain mistakes; the official description above is the record.