---
id: CVE-2026-97957
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: hinic: fix mailbox segment buffer overflow

  check_mbox_seq_id_and_seg_len() validates that seq_id does not
  exceed SEQ_ID_MAX_VAL (42) and seg_len does not exceed
  M…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: hinic: fix mailbox segment buffer overflow

  check_mbox_seq_id_and_seg_len() validates that seq_id does not
  exceed SEQ_ID_MAX_VAL (42) and seg_len does not exceed
  M…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= a425b6e1c69ba907b72b737a4d44f8cfbc43ce3c <
    eca54a092d5f7b497b458ff5a6f66d4f7bfb6674
  - >-
    Linux >= a425b6e1c69ba907b72b737a4d44f8cfbc43ce3c <
    9f6ad383901d0cb1c8ea5f7f3160fabfe1540eb5
  - >-
    Linux >= a425b6e1c69ba907b72b737a4d44f8cfbc43ce3c <
    513f7b16ed0cffae9348151c72bed17c7073096f
  - >-
    Linux >= a425b6e1c69ba907b72b737a4d44f8cfbc43ce3c <
    5d4d985957434867bbe85e4fa5e638f3e48ad522
  - Linux 5.8
published: '2026-09-25'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T15:18:03.100'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97957'
references:
  - url: 'https://git.kernel.org/stable/c/513f7b16ed0cffae9348151c72bed17c7073096f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5d4d985957434867bbe85e4fa5e638f3e48ad522'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9f6ad383901d0cb1c8ea5f7f3160fabfe1540eb5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/eca54a092d5f7b497b458ff5a6f66d4f7bfb6674'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-25T11:06:38.876Z'
---

## Overview

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

net: hinic: fix mailbox segment buffer overflow

check_mbox_seq_id_and_seg_len() validates that seq_id does not
exceed SEQ_ID_MAX_VAL (42) and seg_len does not exceed
MBOX_SEG_LEN (48).  However, this allows the last segment
(seq_id=42) to carry a full 48-byte payload, writing to offset
42*48=2016 for 48 bytes (ending at byte 2064).  The receive
buffer is only MBOX_MAX_BUF_SZ (2048) bytes, resulting in a
16-byte heap buffer overflow.

The hinic3 driver already handles this correctly by defining
MBOX_LAST_SEG_MAX_LEN and rejecting the last segment when it
exceeds the remaining buffer space.  Apply the same fix to the
hinic driver.

## Remediation

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