CVE-2021-33779 Windows AD FS Security Feature Bypass Vulnerability
High 8.1
Published
Updated
Check this codebase for CVE-2021-33779 and fix it if it is affected.
What it is: CVE-2021-33779 is a high-severity vulnerability in Microsoft Windows Server 2016, published on 14 Jul 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-33779 in the wild and no public exploit code.
Affected product: Microsoft Windows Server 2016. 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-2021-33779/ (Markdown: https://insights.sbomify.com/CVE-2021-33779/index.md)
Attackers can bypass security features in Windows AD FS, potentially compromising authentication integrity on affected Windows Server installations.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-33779?
CVE-2021-33779 is a high-severity vulnerability in Microsoft Windows Server 2016, published on 14 Jul 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Windows AD FS Security Feature Bypass Vulnerability
Which versions are affected by CVE-2021-33779?
It affects 2 products.
Products include Microsoft Windows Server 2016, Microsoft Windows Server 2019.
How do I fix CVE-2021-33779?
No fix has been published for CVE-2021-33779 yet. Limit exposure of the affected software until one is available.
Is CVE-2021-33779 being exploited?
There is no known exploitation of CVE-2021-33779 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows Server 2016
- CVE-2021-34458 Windows Kernel Remote Code Execution Vulnerability
- CVE-2024-38076 Windows Remote Desktop Licensing Service Remote Code Execution Vulnerability
- CVE-2026-27928 Windows Hello Security Feature Bypass Vulnerability
- CVE-2025-27482 Windows Remote Desktop Services Remote Code Execution Vulnerability
- CVE-2024-49106 Windows Remote Desktop Services Remote Code Execution Vulnerability
Sources
Also known as GHSA-jgpr-7x8j-xjhf.