# CVE-2026-99118: drm/i915/dmc: Harden DMC firmware payload parsing


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** AZL-111218, BELL-CVE-2026-99118, DEBIAN-CVE-2026-99118, GHSA-v3g3-p6wj-rwgr, UBUNTU-CVE-2026-99118

## What is CVE-2026-99118?

CVE-2026-99118 is a vulnerability in Linux, published on 28 Oct 2026. 

### Official description

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

drm/i915/dmc: Harden DMC firmware payload parsing

Validate the conversion of the DMC firmware size from dwords to bytes
using check_mul_overflow() before calculating the firmware payload size.

Reject zero-length payloads and zero MMIO counts in the DMC firmware
header so malformed firmware is caught early. Also set dmc_fw_size only
after the payload allocation succeeds.

(cherry picked from commit efde6601a1f1daedfe3dcc2816c934ddb44e3eef)

## Which versions are affected by CVE-2026-99118?


## How do I fix CVE-2026-99118?

Upgrade to a fixed version.

## Is CVE-2026-99118 being exploited?

There is no known exploitation of CVE-2026-99118 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-99118 and fix it if it is affected.

What it is: CVE-2026-99118 is a vulnerability in Linux, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-99118 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-2026-99118/ (Markdown: https://insights.sbomify.com/CVE-2026-99118/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-99118
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-99118
- OSV: https://osv.dev/vulnerability/CVE-2026-99118

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-99118/
Summaries are generated and may contain mistakes; the official description above is the record.