# CVE-2021-36949: Microsoft Azure Active Directory Connect Authentication Bypass Vulnerability

> Attackers can bypass authentication in Azure AD Connect, potentially gaining unauthorized access to identity synchronization services.

- **Severity:** High 7.1 (`CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/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:** 12 Aug 2021
- **Updated:** 10 Aug 2026
- **Also known as:** GHSA-55wf-38cw-5f72

## What is CVE-2021-36949?

CVE-2021-36949 is a high-severity authentication bypass vulnerability in Microsoft Azure Active Directory Connect Provisioning Agent, published on 12 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Microsoft Azure Active Directory Connect Authentication Bypass Vulnerability

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2021-36949?

It affects 2 products.


Products: Microsoft Azure Active Directory Connect, Microsoft Azure Active Directory Connect Provisioning Agent.

## How do I fix CVE-2021-36949?

No fix has been published for CVE-2021-36949 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-36949 being exploited?

There is no known exploitation of CVE-2021-36949 in the wild and no public exploit code.

Public exploit code:

- check if Azure AD Connect is affected by the vulnerability described in CVE-2021-36949 (github_poc): https://github.com/Maxwitat/Check-AAD-Connect-for-CVE-2021-36949-vulnerability

## Other vulnerabilities in Microsoft Azure Active Directory Connect Provisioning Agent

- [CVE-2017-8613](https://insights.sbomify.com/CVE-2017-8613/): Privilege escalation in Azure AD Connect (high 8.1)
- [CVE-2019-1000](https://insights.sbomify.com/CVE-2019-1000/): Privilege escalation in Microsoft Azure Active Directory Connect (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-36949 and fix it if it is affected.

What it is: CVE-2021-36949 is a high-severity authentication bypass vulnerability in Microsoft Azure Active Directory Connect Provisioning Agent, published on 12 Aug 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-2021-36949 in the wild and no public exploit code.

Affected product: Microsoft Azure Active Directory Connect Provisioning Agent. 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-2021-36949/ (Markdown: https://insights.sbomify.com/CVE-2021-36949/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-36949
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-36949
- OSV: https://osv.dev/vulnerability/CVE-2021-36949

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-36949/
Summaries are generated and may contain mistakes; the official description above is the record.