# CVE-2026-45461: Microsoft Office Remote Code Execution Vulnerability

> An attacker can execute arbitrary code locally via a use-after-free vulnerability in Microsoft Office applications.

- **Severity:** High 8.4 (`CVSS:3.1/AV:L/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Jun 2026
- **Updated:** 24 Sep 2026
- **Also known as:** GHSA-3c5w-7g69-r2hm

## What is CVE-2026-45461?

CVE-2026-45461 is a high-severity use after free vulnerability in Microsoft 365 Apps, published on 9 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.

Weakness: CWE-787 (Out-of-bounds Write), CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-45461?

It affects 7 products.


Products: Microsoft 365 Apps, Microsoft 365 Copilot, Microsoft Microsoft 365, Microsoft Office 2016, Microsoft Office 2019, Microsoft Office 2021, Microsoft Office 2024.

## How do I fix CVE-2026-45461?

No fix has been published for CVE-2026-45461 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-45461 being exploited?

There is no known exploitation of CVE-2026-45461 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-2026-45461 and fix it if it is affected.

What it is: CVE-2026-45461 is a high-severity use after free vulnerability in Microsoft 365 Apps, published on 9 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-45461 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-2026-45461/ (Markdown: https://insights.sbomify.com/CVE-2026-45461/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-45461
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-45461
- OSV: https://osv.dev/vulnerability/CVE-2026-45461

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-45461/
Summaries are generated and may contain mistakes; the official description above is the record.