---
id: CVE-2026-14258
title: >-
  Dhcpcd: dhcpcd infinite loop and out-of-bounds read via zero-length ipv6 nd
  option in router advertisement handling
summary: >-
  A flaw was found in dhcpcd's IPv6 Neighbor Discovery Router Advertisement
  processing. A specially crafted IPv6 Router Advertisement containing a
  zero-length Neighbor Discovery option can bypass validation during packet
  storage and later …
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: cna
cwe:
  - CWE-835
vendor: Red Hat
product: dhcpcd
affected:
  - dhcpcd (all versions)
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-07-01T12:20:39.579180Z'
exploitAvailable: true
published: '2026-07-01'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T16:40:56.406Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-14258'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:54210'
    label: 'RHSA-2026:54210'
  - url: 'https://access.redhat.com/security/cve/CVE-2026-14258'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2462305'
    label: RHBZ#2462305
  - url: 'https://github.com/NetworkConfiguration/dhcpcd/commit/75289ca'
  - url: 'https://github.com/NetworkConfiguration/dhcpcd/issues/415'
tags:
  - cve.org
  - exploit-available
epss: 0.00397
epssPercentile: 0.34122
ingestedAt: '2026-11-05T22:38:31.380Z'
---

## Overview

A flaw was found in dhcpcd's IPv6 Neighbor Discovery Router Advertisement processing. A specially crafted IPv6 Router Advertisement containing a zero-length Neighbor Discovery option can bypass validation during packet storage and later be reparsed without adequate validation, causing the parser to enter a non-advancing loop. Successful exploitation may result in excessive CPU consumption, leading to a denial of service.

## Affected

- `dhcpcd (all versions)`

## Remediation

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

### Workarounds

Until an updated package is available, administrators should disable IPv6 Router Advertisement processing on interfaces where it is not required or restrict acceptance of untrusted ICMPv6 Router Advertisements using appropriate network filtering. 

Systems that rely on IPv6 Stateless Address Autoconfiguration (SLAAC) or Router Advertisement-based network configuration should carefully evaluate the operational impact before applying these mitigations.