# CVE-2024-6383: MongoDB C Driver bson_string_append may be vulnerable to a buffer overflow

> A buffer overflow in the MongoDB C Driver's bson_string_append function allows attackers to corrupt heap memory, potentially leading to code execution or crashes.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 3 Jul 2024
- **Updated:** 3 Nov 2025
- **Also known as:** DEBIAN-CVE-2024-6383, GHSA-w25p-2jj3-j5vr, OESA-2024-1880, UBUNTU-CVE-2024-6383

## What is CVE-2024-6383?

CVE-2024-6383 is a medium-severity memory corruption vulnerability in MongoDB Inc libbson, published on 3 Jul 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The bson_string_append function in MongoDB C Driver may be vulnerable to a buffer overflow where the function might attempt to allocate too small of buffer and may lead to memory corruption of neighbouring heap memory. This issue affects libbson versions prior to 1.27.1

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2024-6383?


## How do I fix CVE-2024-6383?

Upgrade to a fixed version.

## Is CVE-2024-6383 being exploited?

There is no known exploitation of CVE-2024-6383 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-6383 and fix it if it is affected.

What it is: CVE-2024-6383 is a medium-severity memory corruption vulnerability in MongoDB Inc libbson, published on 3 Jul 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-2024-6383 in the wild and no public exploit code.

Affected product: MongoDB Inc libbson. 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-2024-6383/ (Markdown: https://insights.sbomify.com/CVE-2024-6383/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-6383
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-6383
- OSV: https://osv.dev/vulnerability/CVE-2024-6383

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-6383/
Summaries are generated and may contain mistakes; the official description above is the record.