# CVE-2026-74355: iommu/vt-d: Fix RB-tree corruption in probe error path

> A flaw in the Linux kernel's IOMMU driver allows memory corruption during device probe failures, potentially leading to system crashes or arbitrary code execution.

- **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:** 15 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** BELL-CVE-2026-74355, DEBIAN-CVE-2026-74355, GHSA-444c-98p8-5jq5, UBUNTU-CVE-2026-74355

## What is CVE-2026-74355?

CVE-2026-74355 is a high-severity memory corruption vulnerability in Linux, published on 15 Aug 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: Fix RB-tree corruption in probe error path

The info->node RB-tree member is zero-initialized via kzalloc. If
a device does not support ATS, the device_rbtree_insert() call is
skipped. If a subsequent probe step fails, the error path jumps to
device_rbtree_remove(), which misinterprets the zeroed node as
a tree root and corrupts the device RB-tree.

Fix this by explicitly initializing the RB-node as empty using
RB_CLEAR_NODE() during initialization and guarding the removal with
RB_EMPTY_NODE().

## Which versions are affected by CVE-2026-74355?


## How do I fix CVE-2026-74355?

Apply the vendor's patch.

## Is CVE-2026-74355 being exploited?

There is no known exploitation of CVE-2026-74355 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74355 and fix it if it is affected.

What it is: CVE-2026-74355 is a high-severity memory corruption vulnerability in Linux, published on 15 Aug 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-2026-74355 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-2026-74355/ (Markdown: https://insights.sbomify.com/CVE-2026-74355/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74355
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74355
- OSV: https://osv.dev/vulnerability/CVE-2026-74355

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74355/
Summaries are generated and may contain mistakes; the official description above is the record.