---
id: CVE-2026-99118
title: 'drm/i915/dmc: Harden DMC firmware payload parsing'
summary: |-
  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 t…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= eb805623d8b161342ed9c9caf366f0a295041a6d <
    dfcfe2874e7c16e8460dc86ac1eeb54ea0e7f8aa
  - >-
    Linux >= eb805623d8b161342ed9c9caf366f0a295041a6d <
    05f7a2f712f8b287a98ee61a7c2c6b72dad2fc6d
  - >-
    Linux >= eb805623d8b161342ed9c9caf366f0a295041a6d <
    8bb1858db453cd4250e3b633f5d2d09206024ca6
  - Linux 4.2
published: '2026-10-28'
updated: '2026-10-28'
sourceUpdated: '2026-10-28T10:34:34.627Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-99118'
references:
  - url: 'https://git.kernel.org/stable/c/dfcfe2874e7c16e8460dc86ac1eeb54ea0e7f8aa'
  - url: 'https://git.kernel.org/stable/c/05f7a2f712f8b287a98ee61a7c2c6b72dad2fc6d'
  - url: 'https://git.kernel.org/stable/c/8bb1858db453cd4250e3b633f5d2d09206024ca6'
tags:
  - cve.org
ingestedAt: '2026-10-28T11:09:40.449Z'
---

## Overview

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)

## Affected

- `Linux >= eb805623d8b161342ed9c9caf366f0a295041a6d < dfcfe2874e7c16e8460dc86ac1eeb54ea0e7f8aa`
- `Linux >= eb805623d8b161342ed9c9caf366f0a295041a6d < 05f7a2f712f8b287a98ee61a7c2c6b72dad2fc6d`
- `Linux >= eb805623d8b161342ed9c9caf366f0a295041a6d < 8bb1858db453cd4250e3b633f5d2d09206024ca6`
- `Linux 4.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.