# CVE-2024-41006: netrom: Fix a memory leak in nr_heartbeat_expiry()

> A memory leak in the Linux kernel's netrom module allows attackers to cause a denial of service by exhausting system memory.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Jul 2024
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2024-41006, DEBIAN-CVE-2024-41006, GHSA-xp5x-wr7x-fp9j, UBUNTU-CVE-2024-41006

## What is CVE-2024-41006?

CVE-2024-41006 is a medium-severity denial of service vulnerability in Linux kernel, published on 12 Jul 2024. 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:

netrom: Fix a memory leak in nr_heartbeat_expiry()

syzbot reported a memory leak in nr_create() [0].

Commit 409db27e3a2e ("netrom: Fix use-after-free of a listening socket.")
added sock_hold() to the nr_heartbeat_expiry() function, where
a) a socket has a SOCK_DESTROY flag or
b) a listening socket has a SOCK_DEAD flag.

But in the case "a," when the SOCK_DESTROY flag is set, the file descriptor
has already been closed and the nr_release() function has been called.
So it makes no sense to hold the reference count because no one will
call another nr_destroy_socket() and put it as in the case "b."

nr_connect
  nr_establish_data_link
    nr_start_heartbeat

nr_release
  switch (nr->state)
  case NR_STATE_3
    nr->state = NR_STATE_2
    sock_set_flag(sk, SOCK_DESTROY);

                        nr_rx_frame
                          nr_process_rx_frame
                            switch (nr->state)
                            case NR_STATE_2
                              nr_state2_machine()
                                nr_disconnect()
                                  nr_sk(sk)->state = NR_STATE_0
                                  sock_set_flag(sk, SOCK_DEAD)

                        nr_heartbeat_expiry
                          switch (nr->state)
                          case NR_STATE_0
                            if (sock_flag(sk, SOCK_DESTROY) ||
                               (sk->sk_state == TCP_LISTEN
                                 && sock_flag(sk, SOCK_DEAD)))
                               sock_hold()  // ( !!! )
                               nr_destroy_socket()

To fix the memory leak, let's call sock_hold() only for a listening socket.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with Syzkaller.

[0]: https://syzkaller.appspot.com/bug?extid=d327a1f3b12e1e206c16

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2024-41006?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-41006?

Apply the vendor's patch.

## Is CVE-2024-41006 being exploited?

There is no known exploitation of CVE-2024-41006 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-2024-41006 and fix it if it is affected.

What it is: CVE-2024-41006 is a medium-severity denial of service vulnerability in Linux kernel, published on 12 Jul 2024. 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-2024-41006 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-2024-41006/ (Markdown: https://insights.sbomify.com/CVE-2024-41006/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-41006
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-41006
- OSV: https://osv.dev/vulnerability/CVE-2024-41006

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-41006/
Summaries are generated and may contain mistakes; the official description above is the record.