# CVE-2023-21716: Microsoft Word Remote Code Execution Vulnerability

> An integer overflow in Microsoft Word allows remote attackers to execute arbitrary code via a specially crafted file.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Feb 2023
- **Updated:** 19 Aug 2026
- **Also known as:** GHSA-64mm-8wcm-jw5g

## What is CVE-2023-21716?

CVE-2023-21716 is a critical vulnerability in Microsoft Office, published on 14 Feb 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Microsoft Word Remote Code Execution Vulnerability

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2023-21716?

It affects 8 products.


Products: Microsoft Office, Microsoft Office Long Term Servicing Channel, Microsoft Office Online Server, Microsoft Office Web Apps, Microsoft Sharepoint Enterprise Server, Microsoft Sharepoint Foundation, Microsoft Sharepoint Server, Microsoft Word.

## How do I fix CVE-2023-21716?

No fix has been published for CVE-2023-21716 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-21716 being exploited?

There is no known exploitation of CVE-2023-21716 in the wild and no public exploit code.

Public exploit code:

- A vulnerability within Microsoft Office's wwlib allows attackers to achieve remote code execution with the privileges of the victim that opens a malicious RTF document. The attacker could deliver this file as an email attachment (or other means). (github_poc): https://github.com/gyaansastra/CVE-2023-21716
- RTF Crash POC Python 3.11 Windows 10 (github_poc): https://github.com/Xnuvers007/CVE-2023-21716
- POC : CVE-2023-21716 Microsoft Word RTF Font Table Heap Corruption (github_poc): https://github.com/JMousqueton/CVE-2023-21716
- test of exploit for CVE-2023-21716 (github_poc): https://github.com/hv0l/CVE-2023-21716_exploit
- https://github.com/FeatherStark/CVE-2023-21716 (github_poc): https://github.com/FeatherStark/CVE-2023-21716
- Proof Of Concept for CVE-2023-21716 Microsoft Word Heap Corruption (github_poc): https://github.com/RonF98/CVE-2023-21716-POC

## Other vulnerabilities in Microsoft Office

- [CVE-2018-0798](https://insights.sbomify.com/CVE-2018-0798/): Microsoft Office Memory Corruption (high 8.8, exploited in the wild)
- [CVE-2015-1770](https://insights.sbomify.com/CVE-2015-1770/): Microsoft Office Uninitialized Memory Use (high 8.8, exploited in the wild)
- [CVE-2006-2492](https://insights.sbomify.com/CVE-2006-2492/): Microsoft Word Malformed Object Pointer (high 8.8, exploited in the wild)
- [CVE-2018-0802](https://insights.sbomify.com/CVE-2018-0802/): Microsoft Office Memory Corruption (high 7.8, exploited in the wild)
- [CVE-2017-11882](https://insights.sbomify.com/CVE-2017-11882/): Microsoft Office Memory Corruption (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-21716 and fix it if it is affected.

What it is: CVE-2023-21716 is a critical vulnerability in Microsoft Office, published on 14 Feb 2023. 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-2023-21716 in the wild and no public exploit code.

Affected product: Microsoft Office. 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-2023-21716/ (Markdown: https://insights.sbomify.com/CVE-2023-21716/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-21716
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-21716
- OSV: https://osv.dev/vulnerability/CVE-2023-21716

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-21716/
Summaries are generated and may contain mistakes; the official description above is the record.