# CVE-2024-20677: Microsoft Office Remote Code Execution Vulnerability

> A memory corruption vulnerability in FBX file handling allows remote code execution in Microsoft Office and 3D Viewer.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 9 Jan 2024
- **Updated:** 3 May 2025
- **Also known as:** GHSA-9cx9-hjrh-cgmm

## What is CVE-2024-20677?

CVE-2024-20677 is a high-severity memory corruption vulnerability in Microsoft 365 Apps, published on 9 Jan 2024. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

A security vulnerability exists in FBX that could lead to remote code execution. To mitigate this vulnerability, the ability to insert FBX files has been disabled in Word, Excel, PowerPoint and Outlook for Windows and Mac. Versions of Office that had this feature enabled will no longer have access to it. This includes Office 2019, Office 2021, Office LTSC for Mac 2021, and Microsoft 365. As of February 13, 2024, the ability to insert FBX files has also been disabled in 3D Viewer.
3D models in Office documents that were previously inserted from a FBX file will continue to work as expected unless the Link to File option was chosen at insert time.
This change is effective as of the January 9, 2024 security update.

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

## Which versions are affected by CVE-2024-20677?

It affects 3 products.


Products: Microsoft 365 Apps, Microsoft Office, Microsoft Office Long Term Servicing Channel.

## How do I fix CVE-2024-20677?

No fix has been published for CVE-2024-20677 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-20677 being exploited?

There is no known exploitation of CVE-2024-20677 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft 365 Apps

- [CVE-2024-21413](https://insights.sbomify.com/CVE-2024-21413/): Microsoft Outlook Improper Input Validation (critical 9.8, exploited in the wild)
- [CVE-2023-23397](https://insights.sbomify.com/CVE-2023-23397/): Microsoft Office Outlook Privilege Escalation (critical 9.8, exploited in the wild)
- [CVE-2024-38189](https://insights.sbomify.com/CVE-2024-38189/): Microsoft Project Remote Code Execution Vulnerability (high 8.8, exploited in the wild)
- [CVE-2023-35311](https://insights.sbomify.com/CVE-2023-35311/): Microsoft Outlook Security Feature Bypass (high 8.8, exploited in the wild)
- [CVE-2026-21514](https://insights.sbomify.com/CVE-2026-21514/): Microsoft Office Word Reliance on Untrusted Inputs in a Security Decision (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-20677 and fix it if it is affected.

What it is: CVE-2024-20677 is a high-severity memory corruption vulnerability in Microsoft 365 Apps, published on 9 Jan 2024. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2024-20677 in the wild and no public exploit code.

Affected product: Microsoft 365 Apps. 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-2024-20677/ (Markdown: https://insights.sbomify.com/CVE-2024-20677/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-20677
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-20677
- OSV: https://osv.dev/vulnerability/CVE-2024-20677

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-20677/
Summaries are generated and may contain mistakes; the official description above is the record.