# CVE-2026-68354: firewire: net: Fix fragmented datagram reassembly

> A null pointer dereference in the Linux kernel's FireWire network driver can cause a denial of service during fragmented datagram reassembly.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-68354, DEBIAN-CVE-2026-68354, GHSA-pcmh-x4q7-gxf9, UBUNTU-CVE-2026-68354

## What is CVE-2026-68354?

CVE-2026-68354 is a high-severity vulnerability in Linux, published on 10 Aug 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:

firewire: net: Fix fragmented datagram reassembly

fwnet_frag_new() keeps a sorted list of received fragments for a partial
datagram. When a new fragment is adjacent to an existing fragment, the
code checks whether the new fragment also closes the gap to the next or
previous list entry.

Those neighbor lookups currently assume that the current fragment always
has a real next or previous fragment. At a list edge, the next or
previous entry is the list head, not a struct fwnet_fragment_info.

The gap checks also compare against the old edge of the current fragment
instead of the edge after adding the new fragment. As a result, a
fragment that bridges two existing ranges may leave two adjacent ranges
unmerged, so fwnet_pd_is_complete() can miss a complete datagram.

Check for the list head before looking up the neighboring fragment, and
compare the neighbor against the new fragment's far edge when deciding
whether to merge all three ranges.

This issue was found by a static analysis checker and confirmed by
manual source review.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-68354?


## How do I fix CVE-2026-68354?

Apply the vendor's patch.

## Is CVE-2026-68354 being exploited?

There is no known exploitation of CVE-2026-68354 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68354 and fix it if it is affected.

What it is: CVE-2026-68354 is a high-severity vulnerability in Linux, published on 10 Aug 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-2026-68354 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-2026-68354/ (Markdown: https://insights.sbomify.com/CVE-2026-68354/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68354
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68354
- OSV: https://osv.dev/vulnerability/CVE-2026-68354

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68354/
Summaries are generated and may contain mistakes; the official description above is the record.