# CVE-2026-90241: iommu/vt-d: Tear down scalable-mode context on probe failure

> A use-after-free in the Linux kernel IOMMU driver allows attackers to cause denial of service or execute code via crafted PCI device probing.

- **Severity:** High 8.2 (`CVSS:3.1/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:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-90241, DEBIAN-CVE-2026-90241, GHSA-pxrf-9x6q-c744, UBUNTU-CVE-2026-90241

## What is CVE-2026-90241?

CVE-2026-90241 is a high-severity use after free vulnerability in Linux, published on 17 Sep 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/vt-d: Tear down scalable-mode context on probe failure

intel_pasid_setup_sm_context() walks a PCI device’s DMA aliases via
pci_for_each_dma_alias() and programs a scalable-mode context entry for
each RID. For a device with a dma_alias_mask, the callback is invoked
once for the device’s own RID and once for each alias bit, all with the
same pci_dev, so device_pasid_table_setup() runs for multiple RIDs.

pci_for_each_dma_alias() stops at the first callback error. Therefore, a
failure partway through the walk can leave context entries for already
processed RIDs present and still pointing to the device’s PASID table.

On this error path, intel_iommu_probe_device() currently jumps directly
to intel_pasid_free_table(), which frees the PASID table without
first tearing down those context entries. The IOMMU may then walk a
present context entry whose PASID table pointer references freed
memory.

intel_iommu_release_device() already performs teardown before freeing the
table. Apply the same ordering on the probe failure path.

device_pasid_table_teardown() safely handles RIDs that were never
programmed: iommu_context_addr() returns NULL when no context table has
been allocated, and clearing the Present bit of an already non-present
entry is a no-op. So unwind is safe for both the alias that failed and
any aliases not yet reached.

## Which versions are affected by CVE-2026-90241?


## How do I fix CVE-2026-90241?

Apply the vendor's patch.

## Is CVE-2026-90241 being exploited?

There is no known exploitation of CVE-2026-90241 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90241 and fix it if it is affected.

What it is: CVE-2026-90241 is a high-severity use after free vulnerability in Linux, published on 17 Sep 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-2026-90241 in the wild and no public exploit code.

Affected product: Linux. 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-2026-90241/ (Markdown: https://insights.sbomify.com/CVE-2026-90241/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90241
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90241
- OSV: https://osv.dev/vulnerability/CVE-2026-90241

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90241/
Summaries are generated and may contain mistakes; the official description above is the record.