# CVE-2011-1936: Denial of service in n/a

> Local guest users can crash the guest VM by exploiting improper CPUID instruction emulation in Xen on Intel processors.

- **Severity:** Medium 4.6 (`AV:A/AC:H/Au:N/C:N/I:N/A: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:** Yes
- **Published:** 7 Jan 2014
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-36h3-x748-qfw8

## What is CVE-2011-1936?

CVE-2011-1936 is a medium-severity denial of service vulnerability in Xen Xen, published on 7 Jan 2014. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Xen, when using x86 Intel processors and the VMX virtualization extension is enabled, does not properly handle cpuid instruction emulation when exiting the VM, which allows local guest users to cause a denial of service (guest crash) via unspecified vectors.

## Which versions are affected by CVE-2011-1936?

It affects 1 product.


Products: Xen Xen.

## How do I fix CVE-2011-1936?

Apply the vendor's patch.

## Is CVE-2011-1936 being exploited?

There is no known exploitation of CVE-2011-1936 in the wild and no public exploit code.

## Other vulnerabilities in Xen Xen

- [CVE-2017-10912](https://insights.sbomify.com/CVE-2017-10912/): Privilege escalation in n/a (critical 10.0)
- [CVE-2017-10918](https://insights.sbomify.com/CVE-2017-10918/): Memory corruption in n/a (critical 10.0)
- [CVE-2017-10920](https://insights.sbomify.com/CVE-2017-10920/): Memory corruption in n/a (critical 10.0)
- [CVE-2017-10921](https://insights.sbomify.com/CVE-2017-10921/): Memory corruption in n/a (critical 10.0)
- [CVE-2025-27466](https://insights.sbomify.com/CVE-2025-27466/): Mutiple vulnerabilities in the Viridian interface (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-1936 and fix it if it is affected.

What it is: CVE-2011-1936 is a medium-severity denial of service vulnerability in Xen Xen, published on 7 Jan 2014. 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-2011-1936 in the wild and no public exploit code.

Affected product: Xen Xen. 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-2011-1936/ (Markdown: https://insights.sbomify.com/CVE-2011-1936/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-1936
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-1936
- OSV: https://osv.dev/vulnerability/CVE-2011-1936

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-1936/
Summaries are generated and may contain mistakes; the official description above is the record.