# CVE-2021-28321: Diagnostics Hub Standard Collector Service Elevation of Privilege Vulnerability

> An attacker can exploit a symlink vulnerability in the Diagnostics Hub Standard Collector Service to gain elevated privileges on Windows systems.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C`)
- **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:** 13 Apr 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-mjr6-7m42-xgpp

## What is CVE-2021-28321?

CVE-2021-28321 is a high-severity vulnerability in Microsoft Visual Studio, published on 13 Apr 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Diagnostics Hub Standard Collector Service Elevation of Privilege Vulnerability

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

## Which versions are affected by CVE-2021-28321?

It affects 6 products.


Products: Microsoft Visual Studio, Microsoft Visual Studio 2017, Microsoft Visual Studio 2019, Microsoft Windows 10, Microsoft Windows Server 2016, Microsoft Windows Server 2019.

## How do I fix CVE-2021-28321?

No fix has been published for CVE-2021-28321 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-28321 being exploited?

There is no known exploitation of CVE-2021-28321 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft Visual Studio

- [CVE-2025-49739](https://insights.sbomify.com/CVE-2025-49739/): Visual Studio Elevation of Privilege Vulnerability (high 8.8)
- [CVE-2022-35777](https://insights.sbomify.com/CVE-2022-35777/): Visual Studio Remote Code Execution Vulnerability (high 8.8)
- [CVE-2022-35825](https://insights.sbomify.com/CVE-2022-35825/): Visual Studio Remote Code Execution Vulnerability (high 8.8)
- [CVE-2022-35826](https://insights.sbomify.com/CVE-2022-35826/): Visual Studio Remote Code Execution Vulnerability (high 8.8)
- [CVE-2022-35827](https://insights.sbomify.com/CVE-2022-35827/): Visual Studio Remote Code Execution Vulnerability (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-28321 and fix it if it is affected.

What it is: CVE-2021-28321 is a high-severity vulnerability in Microsoft Visual Studio, published on 13 Apr 2021. 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-2021-28321 in the wild and no public exploit code.

Affected product: Microsoft Visual Studio. 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-2021-28321/ (Markdown: https://insights.sbomify.com/CVE-2021-28321/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-28321
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-28321
- OSV: https://osv.dev/vulnerability/CVE-2021-28321

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-28321/
Summaries are generated and may contain mistakes; the official description above is the record.