# CVE-2025-71089: iommu: disable SVA when CONFIG_X86 is set

> Attackers can exploit stale IOMMU cache entries in SVA contexts to achieve privilege escalation or data corruption via use-after-free conditions.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/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:** 13 Jan 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-74330, BELL-CVE-2025-71089, DEBIAN-CVE-2025-71089, GHSA-r6cc-j9rp-4f85, ROOT-OS-DEBIAN-11-CVE-2025-71089, ROOT-OS-DEBIAN-12-CVE-2025-71089, ROOT-OS-DEBIAN-13-CVE-2025-71089, ROOT-OS-UBUNTU-2204-CVE-2025-71089, ROOT-OS-UBUNTU-2404-CVE-2025-71089, UBUNTU-CVE-2025-71089

## What is CVE-2025-71089?

CVE-2025-71089 is a high-severity use after free vulnerability in Linux kernel, published on 13 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

iommu: disable SVA when CONFIG_X86 is set

Patch series "Fix stale IOTLB entries for kernel address space", v7.

This proposes a fix for a security vulnerability related to IOMMU Shared
Virtual Addressing (SVA).  In an SVA context, an IOMMU can cache kernel
page table entries.  When a kernel page table page is freed and
reallocated for another purpose, the IOMMU might still hold stale,
incorrect entries.  This can be exploited to cause a use-after-free or
write-after-free condition, potentially leading to privilege escalation or
data corruption.

This solution introduces a deferred freeing mechanism for kernel page
table pages, which provides a safe window to notify the IOMMU to
invalidate its caches before the page is reused.

This patch (of 8):

In the IOMMU Shared Virtual Addressing (SVA) context, the IOMMU hardware
shares and walks the CPU's page tables.  The x86 architecture maps the
kernel's virtual address space into the upper portion of every process's
page table.  Consequently, in an SVA context, the IOMMU hardware can walk
and cache kernel page table entries.

The Linux kernel currently lacks a notification mechanism for kernel page
table changes, specifically when page table pages are freed and reused. 
The IOMMU driver is only notified of changes to user virtual address
mappings.  This can cause the IOMMU's internal caches to retain stale
entries for kernel VA.

Use-After-Free (UAF) and Write-After-Free (WAF) conditions arise when
kernel page table pages are freed and later reallocated.  The IOMMU could
misinterpret the new data as valid page table entries.  The IOMMU might
then walk into attacker-controlled memory, leading to arbitrary physical
memory DMA access or privilege escalation.  This is also a
Write-After-Free issue, as the IOMMU will potentially continue to write
Accessed and Dirty bits to the freed memory while attempting to walk the
stale page tables.

Currently, SVA contexts are unprivileged and cannot access kernel
mappings.  However, the IOMMU will still walk kernel-only page tables all
the way down to the leaf entries, where it realizes the mapping is for the
kernel and errors out.  This means the IOMMU still caches these
intermediate page table entries, making the described vulnerability a real
concern.

Disable SVA on x86 architecture until the IOMMU can receive notification
to flush the paging cache before freeing the CPU kernel page table pages.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2025-71089?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-71089?

Apply the vendor's patch.

## Is CVE-2025-71089 being exploited?

There is no known exploitation of CVE-2025-71089 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-71089 and fix it if it is affected.

What it is: CVE-2025-71089 is a high-severity use after free vulnerability in Linux kernel, published on 13 Jan 2026. 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-2025-71089 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2025-71089/ (Markdown: https://insights.sbomify.com/CVE-2025-71089/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-71089
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-71089
- OSV: https://osv.dev/vulnerability/CVE-2025-71089

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-71089/
Summaries are generated and may contain mistakes; the official description above is the record.
