# CVE-2015-8550: Race condition in n/a

> Local guest administrators can crash the host or gain privileges via a double fetch race condition in Xen PV backends.

- **Severity:** High 8.2 (`CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Apr 2016
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2015-8550, GHSA-cv84-8x9g-5qcr, UBUNTU-CVE-2015-8550

## What is CVE-2015-8550?

CVE-2015-8550 is a high-severity vulnerability in Xen Xen, published on 14 Apr 2016. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Xen, when used on a system providing PV backends, allows local guest OS administrators to cause a denial of service (host OS crash) or gain privileges by writing to memory shared between the frontend and backend, aka a double fetch vulnerability.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2015-8550?

It affects 2 products.


Products: Novell Suse Linux Enterprise Real Time Extension, Xen Xen.

## How do I fix CVE-2015-8550?

Apply the vendor's patch.

## Is CVE-2015-8550 being exploited?

There is no known exploitation of CVE-2015-8550 in the wild and no public exploit code.

Public exploit code:

- https://github.com/WhatsWrongAndWhy/CVE-2015-8550 (github_poc): https://github.com/WhatsWrongAndWhy/CVE-2015-8550

## Other vulnerabilities in Xen Xen

- [CVE-2015-7833](https://insights.sbomify.com/CVE-2015-7833/): Denial of service in n/a (medium 4.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2015-8550 and fix it if it is affected.

What it is: CVE-2015-8550 is a high-severity vulnerability in Xen Xen, published on 14 Apr 2016. 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-2015-8550 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-2015-8550/ (Markdown: https://insights.sbomify.com/CVE-2015-8550/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2015-8550
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-8550
- OSV: https://osv.dev/vulnerability/CVE-2015-8550

---
From sbomify Insights: https://insights.sbomify.com/CVE-2015-8550/
Summaries are generated and may contain mistakes; the official description above is the record.