---
id: CVE-2026-68400
title: 'firmware: arm_ffa: Fix Endpoint Memory Access Descriptor offset calculation'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  firmware: arm_ffa: Fix Endpoint Memory Access Descriptor offset calculation

  Use the descriptor's `ep_mem_offset` to calculate the start of the endpoint
  memory access a…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 113580530ee7dc61e668b641d657920734533b9f <
    6e902bea625b710f8bf2f40b4ae4b14fa6a33f13
  - >-
    Linux >= 113580530ee7dc61e668b641d657920734533b9f <
    b39b08e6bee812514b449dc874076890e6b871a0
  - >-
    Linux >= 113580530ee7dc61e668b641d657920734533b9f <
    8ef18f0ab3c0ec1eac77289f5a542bd96a8a6d66
  - >-
    Linux >= 113580530ee7dc61e668b641d657920734533b9f <
    b4d961351aa84fdf0148783fb1f3a1391b8a0adb
  - Linux 6.7
published: '2026-08-10'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T12:43:58.807Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-68400'
references:
  - url: 'https://git.kernel.org/stable/c/6e902bea625b710f8bf2f40b4ae4b14fa6a33f13'
  - url: 'https://git.kernel.org/stable/c/b39b08e6bee812514b449dc874076890e6b871a0'
  - url: 'https://git.kernel.org/stable/c/8ef18f0ab3c0ec1eac77289f5a542bd96a8a6d66'
  - url: 'https://git.kernel.org/stable/c/b4d961351aa84fdf0148783fb1f3a1391b8a0adb'
tags:
  - cve.org
epss: 0.00127
epssPercentile: 0.02141
ingestedAt: '2026-10-21T12:48:53.600Z'
---

## Overview

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

firmware: arm_ffa: Fix Endpoint Memory Access Descriptor offset calculation

Use the descriptor's `ep_mem_offset` to calculate the start of the endpoint
memory access array and to comply with the FF-A spec instead of defaulting
to `sizeof(struct ffa_mem_region)`.
This requires moving `ffa_mem_region_additional_setup()` earlier in the setup
flow.
Also, add sanity checks to ensure the calculated descriptor offsets do not
exceed `max_fragsize`.

## Affected

- `Linux >= 113580530ee7dc61e668b641d657920734533b9f < 6e902bea625b710f8bf2f40b4ae4b14fa6a33f13`
- `Linux >= 113580530ee7dc61e668b641d657920734533b9f < b39b08e6bee812514b449dc874076890e6b871a0`
- `Linux >= 113580530ee7dc61e668b641d657920734533b9f < 8ef18f0ab3c0ec1eac77289f5a542bd96a8a6d66`
- `Linux >= 113580530ee7dc61e668b641d657920734533b9f < b4d961351aa84fdf0148783fb1f3a1391b8a0adb`
- `Linux 6.7`

## Remediation

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