# CVE-2026-62433: correct buffer checks for DM_OP hypercalls

> A missing buffer check in Xen hypervisor DM_OP handling allows attackers to access uninitialized stack memory, potentially leading to code execution or crashes.

- **Severity:** High 7.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Jul 2026
- **Updated:** 28 Jul 2026
- **Also known as:** ALPINE-CVE-2026-62433, DEBIAN-CVE-2026-62433, GHSA-cfmp-p477-x9qv, UBUNTU-CVE-2026-62433

## What is CVE-2026-62433?

CVE-2026-62433 is a high-severity memory corruption vulnerability in Xen, published on 28 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Parts of the DM_OP handling code assumes the caller has provided the
required number of buffers for the given operation without any checking
being done.  As a result, certain operations might access stack
rubble as structures are possibly uninitialized.

Weakness: CWE-665 (Improper Initialization)

## Which versions are affected by CVE-2026-62433?


## How do I fix CVE-2026-62433?

Apply the vendor's patch.

## Is CVE-2026-62433 being exploited?

There is no known exploitation of CVE-2026-62433 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-62433 and fix it if it is affected.

What it is: CVE-2026-62433 is a high-severity memory corruption vulnerability in Xen, published on 28 Jul 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-2026-62433 in the wild and no public exploit code.

Affected product: 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-2026-62433/ (Markdown: https://insights.sbomify.com/CVE-2026-62433/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-62433
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-62433
- OSV: https://osv.dev/vulnerability/CVE-2026-62433

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-62433/
Summaries are generated and may contain mistakes; the official description above is the record.