# CVE-2026-22997: net: can: j1939: j1939_xtp_rx_rts_session_active(): deactivate session upon receiving the second rts

> A refcount leak in the Linux kernel's J1939 CAN protocol implementation can cause a denial of service by preventing network device unregistration.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jan 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-77316, AZL-78479, BELL-CVE-2026-22997, DEBIAN-CVE-2026-22997, GHSA-86mf-f3rq-8369, ROOT-OS-UBUNTU-2204-CVE-2026-22997, ROOT-OS-UBUNTU-2404-CVE-2026-22997, UBUNTU-CVE-2026-22997

## What is CVE-2026-22997?

CVE-2026-22997 is a high-severity denial of service vulnerability in Linux kernel, published on 25 Jan 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:

net: can: j1939: j1939_xtp_rx_rts_session_active(): deactivate session upon receiving the second rts

Since j1939_session_deactivate_activate_next() in j1939_tp_rxtimer() is
called only when the timer is enabled, we need to call
j1939_session_deactivate_activate_next() if we cancelled the timer.
Otherwise, refcount for j1939_session leaks, which will later appear as

| unregister_netdevice: waiting for vcan0 to become free. Usage count = 2.

problem.

Weakness: CWE-772 (Missing Release of Resource after Effective Lifetime)

## Which versions are affected by CVE-2026-22997?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-22997?

Apply the vendor's patch.

## Is CVE-2026-22997 being exploited?

There is no known exploitation of CVE-2026-22997 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-22997 and fix it if it is affected.

What it is: CVE-2026-22997 is a high-severity denial of service vulnerability in Linux kernel, published on 25 Jan 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-2026-22997 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-22997/ (Markdown: https://insights.sbomify.com/CVE-2026-22997/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-22997
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-22997
- OSV: https://osv.dev/vulnerability/CVE-2026-22997

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-22997/
Summaries are generated and may contain mistakes; the official description above is the record.