# CVE-2026-98174: smb: client: fix rlist race and missing initialization

> A race condition and missing initialization in the Linux kernel SMB client can lead to list corruption and potential denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-106391, BELL-CVE-2026-98174, DEBIAN-CVE-2026-98174, GHSA-f559-3m6w-qcp7, UBUNTU-CVE-2026-98174

## What is CVE-2026-98174?

CVE-2026-98174 is a high-severity vulnerability in Linux, published on 6 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

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

smb: client: fix rlist race and missing initialization

TCP_Server_Info.rlist is allocated via kzalloc which zeros both ->next
and ->prev to NULL instead of pointing to itself, making list_empty()
always return false and list_add() dereference a NULL ->prev pointer.

Also, cifs_signal_cifsd_for_reconnect() can be called concurrently
from multiple cifsd threads, allowing the same server's rlist node to
be added twice into the local list, corrupting it.

## Which versions are affected by CVE-2026-98174?


## How do I fix CVE-2026-98174?

Apply the vendor's patch.

## Is CVE-2026-98174 being exploited?

There is no known exploitation of CVE-2026-98174 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98174 and fix it if it is affected.

What it is: CVE-2026-98174 is a high-severity vulnerability in Linux, published on 6 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-98174 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-2026-98174/ (Markdown: https://insights.sbomify.com/CVE-2026-98174/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98174
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98174
- OSV: https://osv.dev/vulnerability/CVE-2026-98174

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98174/
Summaries are generated and may contain mistakes; the official description above is the record.