# CVE-2023-53356: usb: gadget: u_serial: Add null pointer check in gserial_suspend

> A null pointer dereference in the Linux kernel USB gadget serial driver can cause a system crash during suspend operations.

- **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:** 17 Sep 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-53356, DEBIAN-CVE-2023-53356, GHSA-fvf2-2vh9-p4j4, UBUNTU-CVE-2023-53356

## What is CVE-2023-53356?

CVE-2023-53356 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 2025. 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:

usb: gadget: u_serial: Add null pointer check in gserial_suspend

Consider a case where gserial_disconnect has already cleared
gser->ioport. And if gserial_suspend gets called afterwards,
it will lead to accessing of gser->ioport and thus causing
null pointer dereference.

Avoid this by adding a null pointer check. Added a static
spinlock to prevent gser->ioport from becoming null after
the newly added null pointer check.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2023-53356?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-53356?

Apply the vendor's patch.

## Is CVE-2023-53356 being exploited?

There is no known exploitation of CVE-2023-53356 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-2023-53356 and fix it if it is affected.

What it is: CVE-2023-53356 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 2025. 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-2023-53356 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-2023-53356/ (Markdown: https://insights.sbomify.com/CVE-2023-53356/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53356
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53356
- OSV: https://osv.dev/vulnerability/CVE-2023-53356

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53356/
Summaries are generated and may contain mistakes; the official description above is the record.