# CVE-2026-21520: Copilot Studio Information Disclosure Vulnerability

> Unauthenticated attackers can view sensitive information in Microsoft Copilot Studio via network access, requiring a vendor patch.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C/CR:H/IR:L/AR:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Jan 2026
- **Updated:** 30 Jul 2026
- **Also known as:** GHSA-5vx4-v4r5-wrxg

## What is CVE-2026-21520?

CVE-2026-21520 is a high-severity vulnerability in Microsoft Copilot Studio, published on 22 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive information through network attack vector

Weakness: CWE-77 (Improper Neutralization of Special Elements used in a Command)

## Which versions are affected by CVE-2026-21520?

It affects 1 product.


Products: Microsoft Copilot Studio.

## How do I fix CVE-2026-21520?

No fix has been published for CVE-2026-21520 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-21520 being exploited?

There is no known exploitation of CVE-2026-21520 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft Copilot Studio

- [CVE-2026-80098](https://insights.sbomify.com/CVE-2026-80098/): Copilot Studio Elevation of Privilege Vulnerability (critical 9.3)
- [CVE-2024-49038](https://insights.sbomify.com/CVE-2024-49038/): Microsoft Copilot Studio Elevation Of Privilege Vulnerability (critical 9.3)
- [CVE-2024-38206](https://insights.sbomify.com/CVE-2024-38206/): Microsoft Copilot Studio Information Disclosure Vulnerability (high 8.5)
- [CVE-2024-43610](https://insights.sbomify.com/CVE-2024-43610/): Copilot Studio Information Disclosure Vulnerability (high 7.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-21520 and fix it if it is affected.

What it is: CVE-2026-21520 is a high-severity vulnerability in Microsoft Copilot Studio, published on 22 Jan 2026. 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-2026-21520 in the wild and no public exploit code.

Affected product: Microsoft Copilot 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-2026-21520/ (Markdown: https://insights.sbomify.com/CVE-2026-21520/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-21520
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-21520
- OSV: https://osv.dev/vulnerability/CVE-2026-21520

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-21520/
Summaries are generated and may contain mistakes; the official description above is the record.