# CVE-2019-1109: Other in Microsoft Office

> An attacker can spoof web pages to read or write information in Office documents via JavaScript validation flaws.

- **Severity:** Critical 9.1 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Jul 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-j5h9-qc5w-q39g

## What is CVE-2019-1109?

CVE-2019-1109 is a critical vulnerability in Microsoft Office, published on 29 Jul 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A spoofing vulnerability exists when Microsoft Office Javascript does not check the validity of the web page making a request to Office documents.An attacker who successfully exploited this vulnerability could read or write information in Office documents.The security update addresses the vulnerability by correcting the way that Microsoft Office Javascript verifies trusted web pages., aka 'Microsoft Office Spoofing Vulnerability'.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2019-1109?

It affects 2 products.


Products: Microsoft Office, Microsoft Office 365.

## How do I fix CVE-2019-1109?

No fix has been published for CVE-2019-1109 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-1109 being exploited?

There is no known exploitation of CVE-2019-1109 in the wild and no public exploit code.

## 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-2019-1109 and fix it if it is affected.

What it is: CVE-2019-1109 is a critical vulnerability in Microsoft Office, published on 29 Jul 2019. 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-2019-1109 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-2019-1109/ (Markdown: https://insights.sbomify.com/CVE-2019-1109/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-1109
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-1109
- OSV: https://osv.dev/vulnerability/CVE-2019-1109

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-1109/
Summaries are generated and may contain mistakes; the official description above is the record.