# CVE-2023-34326: x86/AMD: missing IOMMU TLB flushing

> Missing IOMMU TLB flushing in Xen allows devices to access unauthorized memory regions via stale DMA mappings, leading to information disclosure.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 5 Jan 2024
- **Updated:** 4 Nov 2025
- **Also known as:** ALPINE-CVE-2023-34326, DEBIAN-CVE-2023-34326, GHSA-mjvw-frxx-6hm5, UBUNTU-CVE-2023-34326

## What is CVE-2023-34326?

CVE-2023-34326 is a high-severity vulnerability in Xen Xen, published on 5 Jan 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The caching invalidation guidelines from the AMD-Vi specification (48882—Rev
3.07-PUB—Oct 2022) is incorrect on some hardware, as devices will malfunction
(see stale DMA mappings) if some fields of the DTE are updated but the IOMMU
TLB is not flushed.

Such stale DMA mappings can point to memory ranges not owned by the guest, thus
allowing access to unindented memory regions.

Weakness: CWE-672 (Operation on a Resource after Expiration or Release)

## Which versions are affected by CVE-2023-34326?

It affects 1 product.


Products: Xen Xen.

## How do I fix CVE-2023-34326?

Apply the vendor's patch.

## Is CVE-2023-34326 being exploited?

There is no known exploitation of CVE-2023-34326 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-2023-34326 and fix it if it is affected.

What it is: CVE-2023-34326 is a high-severity vulnerability in Xen Xen, published on 5 Jan 2024. 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-2023-34326 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-2023-34326/ (Markdown: https://insights.sbomify.com/CVE-2023-34326/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-34326
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-34326
- OSV: https://osv.dev/vulnerability/CVE-2023-34326

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-34326/
Summaries are generated and may contain mistakes; the official description above is the record.