# CVE-2024-42391: Use of Out-of-range Pointer Offset in Mongoose Web Server library

> An attacker can send a malicious TLS packet to trigger an out-of-range pointer offset, causing the application to read unintended heap memory.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 18 Nov 2024
- **Updated:** 8 Sep 2026
- **Also known as:** GHSA-29wp-p54c-r4v7

## What is CVE-2024-42391?

CVE-2024-42391 is a medium-severity memory corruption vulnerability in Cesanta Mongoose, published on 18 Nov 2024. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Use of Out-of-range Pointer Offset vulnerability in Cesanta Mongoose Web Server v7.14 allows an attacker to send an unexpected TLS packet and force the application to read unintended heap memory space.

Weakness: CWE-823 (Use of Out-of-range Pointer Offset)

## Which versions are affected by CVE-2024-42391?

It affects 1 product.


Products: Cesanta Mongoose.

## How do I fix CVE-2024-42391?

No fix has been published for CVE-2024-42391 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-42391 being exploited?

There is no known exploitation of CVE-2024-42391 in the wild and no public exploit code.

## Other vulnerabilities in Cesanta Mongoose

- [CVE-2022-25299](https://insights.sbomify.com/CVE-2022-25299/): Arbitrary File Write (critical 9.8)
- [CVE-2020-25756](https://insights.sbomify.com/CVE-2020-25756/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-19307](https://insights.sbomify.com/CVE-2019-19307/): Integer overflow in n/a (critical 9.8)
- [CVE-2019-12951](https://insights.sbomify.com/CVE-2019-12951/): Memory corruption in n/a (critical 9.8)
- [CVE-2018-20353](https://insights.sbomify.com/CVE-2018-20353/): Use after free in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-42391 and fix it if it is affected.

What it is: CVE-2024-42391 is a medium-severity memory corruption vulnerability in Cesanta Mongoose, published on 18 Nov 2024. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2024-42391 in the wild and no public exploit code.

Affected product: Cesanta Mongoose. 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-2024-42391/ (Markdown: https://insights.sbomify.com/CVE-2024-42391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-42391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-42391
- OSV: https://osv.dev/vulnerability/CVE-2024-42391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-42391/
Summaries are generated and may contain mistakes; the official description above is the record.