# CVE-2020-0891: Cross-site scripting in Microsoft SharePoint Enterprise Server

> An authenticated attacker can execute arbitrary scripts in the victim's browser via a specially crafted request to Microsoft SharePoint Server.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 12 Mar 2020
- **Updated:** 28 Feb 2025
- **Also known as:** GHSA-5c7f-r598-xvcq

## What is CVE-2020-0891?

CVE-2020-0891 is a medium-severity cross-site scripting vulnerability in Microsoft Sharepoint Enterprise Server, published on 12 Mar 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

This vulnerability is caused when SharePoint Server does not properly sanitize a specially crafted request to an affected SharePoint server.An authenticated attacker could exploit this vulnerability by sending a specially crafted request to an affected SharePoint server, aka 'Microsoft SharePoint Reflective XSS Vulnerability'. This CVE ID is unique from CVE-2020-0795.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2020-0891?

It affects 3 products.


Products: Microsoft Sharepoint Enterprise Server, Microsoft Sharepoint Foundation, Microsoft Sharepoint Server.

## How do I fix CVE-2020-0891?

No fix has been published for CVE-2020-0891 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-0891 being exploited?

There is no known exploitation of CVE-2020-0891 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft Sharepoint Enterprise Server

- [CVE-2019-0604](https://insights.sbomify.com/CVE-2019-0604/): Microsoft SharePoint Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2023-24955](https://insights.sbomify.com/CVE-2023-24955/): Microsoft SharePoint Server Code Injection (high 7.2, exploited in the wild)
- [CVE-2025-49706](https://insights.sbomify.com/CVE-2025-49706/): Microsoft SharePoint Improper Authentication (medium 6.5, exploited in the wild)
- [CVE-2020-1210](https://insights.sbomify.com/CVE-2020-1210/): Microsoft SharePoint Remote Code Execution Vulnerability (critical 9.9)
- [CVE-2020-1595](https://insights.sbomify.com/CVE-2020-1595/): Microsoft SharePoint Remote Code Execution Vulnerability (critical 9.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-0891 and fix it if it is affected.

What it is: CVE-2020-0891 is a medium-severity cross-site scripting vulnerability in Microsoft Sharepoint Enterprise Server, published on 12 Mar 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2020-0891 in the wild and no public exploit code.

Affected product: Microsoft Sharepoint Enterprise Server. 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-2020-0891/ (Markdown: https://insights.sbomify.com/CVE-2020-0891/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-0891
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-0891
- OSV: https://osv.dev/vulnerability/CVE-2020-0891

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-0891/
Summaries are generated and may contain mistakes; the official description above is the record.