# CVE-2026-98604: ovpn: replace bind when learning local endpoint

> A race condition in the Linux kernel OVPN module allows concurrent updates to cause torn address reads, potentially leading to denial of service or information disclosure.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-98604, DEBIAN-CVE-2026-98604, GHSA-hmmp-5rq5-qfff, UBUNTU-CVE-2026-98604

## What is CVE-2026-98604?

CVE-2026-98604 is a vulnerability in Linux, published on 18 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

ovpn: replace bind when learning local endpoint

struct ovpn_bind is published through peer->bind with RCU, but local
endpoint learning updates bind->local in place under peer->lock. UDP TX
reads the field without that lock. In particular, a concurrent IPv6
update can therefore result in a torn address read.

Use ovpn_peer_reset_sockaddr to publish a replacement bind when learning
a new local endpoint, just as a remote endpoint change does. Preserve
the current remote address and reset the dst cache only after the new
bind has been published successfully.

Track remote endpoint changes separately so that float notification and
transport-address rehashing remain limited to actual peer floats.

## Which versions are affected by CVE-2026-98604?


## How do I fix CVE-2026-98604?

Apply the vendor's patch.

## Is CVE-2026-98604 being exploited?

There is no known exploitation of CVE-2026-98604 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98604 and fix it if it is affected.

What it is: CVE-2026-98604 is a vulnerability in Linux, published on 18 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98604 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-2026-98604/ (Markdown: https://insights.sbomify.com/CVE-2026-98604/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98604
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98604
- OSV: https://osv.dev/vulnerability/CVE-2026-98604

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98604/
Summaries are generated and may contain mistakes; the official description above is the record.