# CVE-2020-0789: Denial of service in Microsoft Visual Studio 2019

> An attacker can cause a denial of service in the Visual Studio Extension Installer Service by exploiting improper hard link handling.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Mar 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-9p8g-4m8r-qpv5

## What is CVE-2020-0789?

CVE-2020-0789 is a high-severity denial of service vulnerability in Microsoft Visual Studio 2019, published on 12 Mar 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A denial of service vulnerability exists when the Visual Studio Extension Installer Service improperly handles hard links, aka 'Visual Studio Extension Installer Service Denial of Service Vulnerability'.

Weakness: CWE-59 (Improper Link Resolution Before File Access)

## Which versions are affected by CVE-2020-0789?

It affects 1 product.


Products: Microsoft Visual Studio 2019.

## How do I fix CVE-2020-0789?

No fix has been published for CVE-2020-0789 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-0789 being exploited?

There is no known exploitation of CVE-2020-0789 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft Visual Studio 2019

- [CVE-2021-27068](https://insights.sbomify.com/CVE-2021-27068/): Visual Studio Remote Code Execution Vulnerability (high 8.8)
- [CVE-2025-32702](https://insights.sbomify.com/CVE-2025-32702/): Visual Studio Remote Code Execution Vulnerability (high 7.8)
- [CVE-2023-28262](https://insights.sbomify.com/CVE-2023-28262/): Visual Studio Elevation of Privilege Vulnerability (high 7.8)
- [CVE-2025-25003](https://insights.sbomify.com/CVE-2025-25003/): Visual Studio Elevation of Privilege Vulnerability (high 7.3)
- [CVE-2023-36759](https://insights.sbomify.com/CVE-2023-36759/): Visual Studio Elevation of Privilege Vulnerability (medium 6.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-0789 and fix it if it is affected.

What it is: CVE-2020-0789 is a high-severity denial of service vulnerability in Microsoft Visual Studio 2019, published on 12 Mar 2020. 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-2020-0789 in the wild and no public exploit code.

Affected product: Microsoft Visual Studio 2019. 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-2020-0789/ (Markdown: https://insights.sbomify.com/CVE-2020-0789/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-0789
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-0789
- OSV: https://osv.dev/vulnerability/CVE-2020-0789

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-0789/
Summaries are generated and may contain mistakes; the official description above is the record.