---
id: CVE-2026-88833
title: A flaw was found in BusyBox's udhcpc DHCP client
summary: >-
  A flaw was found in BusyBox's udhcpc DHCP client. When processing raw DHCP
  packets, the client replaces the validated packet length with an
  attacker-controlled value from the IP header without re-validating the minimum
  size. This leads t…
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'
cwe:
  - CWE-191
vendor: Red Hat
product: busybox
affected:
  - busybox (all versions)
published: '2026-10-13'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T23:17:02.443'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88833'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-88833'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2531347'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-88833.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-88833'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88833'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00189
epssPercentile: 0.08414
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-16T22:21:57.578888Z'
ingestedAt: '2026-10-13T17:38:53.200Z'
---

## Overview

A flaw was found in BusyBox's udhcpc DHCP client. When processing raw DHCP packets, the client replaces the validated packet length with an attacker-controlled value from the IP header without re-validating the minimum size. This leads to an integer underflow when subtracting header sizes, causing a subsequent memory copy with a massively oversized length. An attacker on the same network segment can send a specially crafted packet to crash the DHCP client, resulting in denial of service and loss of network connectivity.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Hardened Images · no fix planned: Red Hat Hardened Images · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-88833.json)