# CVE-2026-99185: firewire: core: fix race condition in split transaction handling


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-99185, GHSA-xxpr-vg8x-pr7q, UBUNTU-CVE-2026-99185

## What is CVE-2026-99185?

CVE-2026-99185 is a vulnerability in Linux, published on 28 Oct 2026. 

### Official description

In the Linux kernel, the following vulnerability has been resolved:

firewire: core: fix race condition in split transaction handling

For a split transaction, either fw_core_handle_response() or
split_transaction_timeout_callback() may manipulate the same transaction
entry in the pending transaction list. The return value of timer_delete()
is used to determine which function handles the entry. If the transaction
is a split transaction and timer_delete() returns zero, the timeout
callback may already be running. In this case, the response handler must
leave the entry in the list for the timeout callback to remove.

A previous code refactoring broke this behavior, introducing a race
condition in which both functions could process the same transaction.
This could lead to a use-after-free on the transaction initiator side.

Fix the regression by ensuring that the response handler does not process
the transaction when timer_delete() returns zero. The timeout callback is
responsible for removing the entry from the pending transaction list.

## Which versions are affected by CVE-2026-99185?


## How do I fix CVE-2026-99185?

Upgrade to a fixed version.

## Is CVE-2026-99185 being exploited?

There is no known exploitation of CVE-2026-99185 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-99185 and fix it if it is affected.

What it is: CVE-2026-99185 is a vulnerability in Linux, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-99185 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-2026-99185/ (Markdown: https://insights.sbomify.com/CVE-2026-99185/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-99185
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-99185
- OSV: https://osv.dev/vulnerability/CVE-2026-99185

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-99185/
Summaries are generated and may contain mistakes; the official description above is the record.