# CVE-2023-54295: mtd: spi-nor: Fix shift-out-of-bounds in spi_nor_set_erase_type

> A shift-out-of-bounds error in the Linux kernel's SPI NOR flash driver can cause a denial of service when masking erase types.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-54295, DEBIAN-CVE-2023-54295, GHSA-3x4v-mgvj-ccrv, UBUNTU-CVE-2023-54295

## What is CVE-2023-54295?

CVE-2023-54295 is a vulnerability in Linux, published on 30 Dec 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:

mtd: spi-nor: Fix shift-out-of-bounds in spi_nor_set_erase_type

spi_nor_set_erase_type() was used either to set or to mask out an erase
type. When we used it to mask out an erase type a shift-out-of-bounds
was hit:
UBSAN: shift-out-of-bounds in drivers/mtd/spi-nor/core.c:2237:24
shift exponent 4294967295 is too large for 32-bit type 'int'

The setting of the size_{shift, mask} and of the opcode are unnecessary
when the erase size is zero, as throughout the code just the erase size
is considered to determine whether an erase type is supported or not.
Setting the opcode to 0xFF was wrong too as nobody guarantees that 0xFF
is an unused opcode. Thus when masking out an erase type, just set the
erase size to zero. This will fix the shift-out-of-bounds.

[ta: refine changes, new commit message, fix compilation error]

## Which versions are affected by CVE-2023-54295?


## How do I fix CVE-2023-54295?

Apply the vendor's patch.

## Is CVE-2023-54295 being exploited?

There is no known exploitation of CVE-2023-54295 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54295 and fix it if it is affected.

What it is: CVE-2023-54295 is a vulnerability in Linux, published on 30 Dec 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-2023-54295 in the wild and no public exploit code.

Affected product: Linux. 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-2023-54295/ (Markdown: https://insights.sbomify.com/CVE-2023-54295/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54295
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54295
- OSV: https://osv.dev/vulnerability/CVE-2023-54295

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54295/
Summaries are generated and may contain mistakes; the official description above is the record.