# CVE-2024-8938: Memory corruption in Modicon M340 CPU (part numbers BMXP34*)

> A memory corruption vulnerability in Schneider Electric PLCs allows arbitrary code execution via a crafted Modbus request after a Man-In-The-Middle attack.

- **Severity:** Critical 9.2 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Nov 2024
- **Updated:** 13 Nov 2024
- **Also known as:** GHSA-fv43-v7vc-rjjf

## What is CVE-2024-8938?

CVE-2024-8938 is a critical memory corruption vulnerability in Schneider Electric Modicon M340 CPU (part numbers BMXP34*), published on 13 Nov 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability exists that could
cause a potential arbitrary code execution after a successful Man-In-The-Middle attack followed by sending a
crafted Modbus function call to tamper with memory area involved in memory size computation.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2024-8938?


## How do I fix CVE-2024-8938?

No fix has been published for CVE-2024-8938 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-8938 being exploited?

There is no known exploitation of CVE-2024-8938 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-8938 and fix it if it is affected.

What it is: CVE-2024-8938 is a critical memory corruption vulnerability in Schneider Electric Modicon M340 CPU (part numbers BMXP34*), published on 13 Nov 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-8938 in the wild and no public exploit code.

Affected product: Schneider Electric Modicon M340 CPU (part numbers BMXP34*). 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-2024-8938/ (Markdown: https://insights.sbomify.com/CVE-2024-8938/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-8938
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-8938
- OSV: https://osv.dev/vulnerability/CVE-2024-8938

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From sbomify Insights: https://insights.sbomify.com/CVE-2024-8938/
Summaries are generated and may contain mistakes; the official description above is the record.