# CVE-2024-36016: tty: n_gsm: fix possible out-of-bounds in gsm0_receive()

> A remote attacker can trigger an out-of-bounds write in the Linux kernel's n_gsm driver by manipulating mode switches, potentially leading to code execution or system crash.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 29 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-36016, DEBIAN-CVE-2024-36016, UBUNTU-CVE-2024-36016

## What is CVE-2024-36016?

CVE-2024-36016 is a high-severity memory corruption vulnerability in Linux kernel, published on 29 May 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:

tty: n_gsm: fix possible out-of-bounds in gsm0_receive()

Assuming the following:
- side A configures the n_gsm in basic option mode
- side B sends the header of a basic option mode frame with data length 1
- side A switches to advanced option mode
- side B sends 2 data bytes which exceeds gsm->len
  Reason: gsm->len is not used in advanced option mode.
- side A switches to basic option mode
- side B keeps sending until gsm0_receive() writes past gsm->buf
  Reason: Neither gsm->state nor gsm->len have been reset after
  reconfiguration.

Fix this by changing gsm->count to gsm->len comparison from equal to less
than. Also add upper limit checks against the constant MAX_MRU in
gsm0_receive() and gsm1_receive() to harden against memory corruption of
gsm->len and gsm->mru.

All other checks remain as we still need to limit the data according to the
user configuration and actual payload size.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2024-36016?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-36016?

Apply the vendor's patch.

## Is CVE-2024-36016 being exploited?

There is no known exploitation of CVE-2024-36016 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-2024-36016 and fix it if it is affected.

What it is: CVE-2024-36016 is a high-severity memory corruption vulnerability in Linux kernel, published on 29 May 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-2024-36016 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-2024-36016/ (Markdown: https://insights.sbomify.com/CVE-2024-36016/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-36016
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-36016
- OSV: https://osv.dev/vulnerability/CVE-2024-36016

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-36016/
Summaries are generated and may contain mistakes; the official description above is the record.