---
id: CVE-2026-98803
title: 'kernel: net: stmmac: fix rx Scatter-Gather support (CVE-2026-98803)'
summary: >-
  A flaw was found in the Linux kernel's stmmac ethernet driver. When receiving
  network frames larger than the primary buffer size, the Direct Memory Access
  (DMA) engine attempts to write excess data into a secondary receive buffer
  that is n…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-476
vendor: Red Hat
product: Linux
affected:
  - >-
    Linux >= 88ebe2cf7f3fc9da95e0f06483fd58da3e67e675 <
    358d5ac5a5d57ce21c3814c4e3e8f3fbcb7304b4
  - >-
    Linux >= 88ebe2cf7f3fc9da95e0f06483fd58da3e67e675 <
    a7cff44543f66f3a19151060cb549691d191d44c
  - >-
    Linux >= 88ebe2cf7f3fc9da95e0f06483fd58da3e67e675 <
    88095728511e0df9c89528944f5a1762ad298983
  - Linux c4b712d1a814a0535091d99e6cf04d69ac42ef7b
  - Linux >= 5.4.262 < 5.5
  - Linux 5.5
published: '2026-10-18'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T15:23:29+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98803.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98803.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98803'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2555058'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98803'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98803'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98803.mbox
  - url: 'https://git.kernel.org/stable/c/358d5ac5a5d57ce21c3814c4e3e8f3fbcb7304b4'
  - url: 'https://git.kernel.org/stable/c/a7cff44543f66f3a19151060cb549691d191d44c'
  - url: 'https://git.kernel.org/stable/c/88095728511e0df9c89528944f5a1762ad298983'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00166
epssPercentile: 0.05774
ingestedAt: '2026-10-18T16:47:32.481Z'
---

## Overview

A flaw was found in the Linux kernel's stmmac ethernet driver. When receiving network frames larger than the primary buffer size, the Direct Memory Access (DMA) engine attempts to write excess data into a secondary receive buffer that is neither allocated nor mapped for regular frames. An attacker on the local network could send oversized packets to cause a memory translation fault, leading to a system crash and Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98803.json)

**kernel: net: stmmac: fix rx Scatter-Gather support** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-23.

Not affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Refer to the advisory for fix availability.