# CVE-2023-53456: scsi: qla4xxx: Add length check when parsing nlattrs

> A missing length check in the qla4xxx SCSI driver allows an attacker to trigger an out-of-bounds read, potentially leaking heap memory contents.

- **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:** 1 Oct 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-53456, DEBIAN-CVE-2023-53456, GHSA-vp46-h7c5-rj5w, UBUNTU-CVE-2023-53456

## What is CVE-2023-53456?

CVE-2023-53456 is a medium-severity vulnerability in Linux kernel, published on 1 Oct 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:

scsi: qla4xxx: Add length check when parsing nlattrs

There are three places that qla4xxx parses nlattrs:

 - qla4xxx_set_chap_entry()

 - qla4xxx_iface_set_param()

 - qla4xxx_sysfs_ddb_set_param()

and each of them directly converts the nlattr to specific pointer of
structure without length checking. This could be dangerous as those
attributes are not validated and a malformed nlattr (e.g., length 0) could
result in an OOB read that leaks heap dirty data.

Add the nla_len check before accessing the nlattr data and return EINVAL if
the length check fails.

## Which versions are affected by CVE-2023-53456?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-53456?

Apply the vendor's patch.

## Is CVE-2023-53456 being exploited?

There is no known exploitation of CVE-2023-53456 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-2023-53456 and fix it if it is affected.

What it is: CVE-2023-53456 is a medium-severity vulnerability in Linux kernel, published on 1 Oct 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-2023-53456 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-2023-53456/ (Markdown: https://insights.sbomify.com/CVE-2023-53456/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53456
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53456
- OSV: https://osv.dev/vulnerability/CVE-2023-53456

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53456/
Summaries are generated and may contain mistakes; the official description above is the record.