---
id: CVE-2026-123608
title: >-
  Hickory DNS hickory-proto 0.3.1 before 0.26.1 CPU Exhaustion via BinEncoder
  Name Compression
summary: >-
  Hickory DNS hickory-proto from 0.3.1 before 0.26.1 contains a denial of
  service vulnerability in BinEncoder that allows remote attackers to exhaust
  CPU through quadratic-time name compression. Attackers can send malicious DNS
  messages wi…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-407
vendor: hickory-dns
product: hickory-dns
affected:
  - hickory-dns >= 0.3.1 < 0.26.1
published: '2026-11-08'
updated: '2026-11-08'
sourceUpdated: '2026-11-08T01:38:34.124Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-123608'
references:
  - url: >-
      https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-q2qq-hmj6-3wpp
    label: GitHub Security Advisory (GHSA-q2qq-hmj6-3wpp)
  - url: >-
      https://www.vulncheck.com/advisories/hickory-dns-hickory-proto-0.3.1-before-0.26.1-cpu-exhaustion-via-binencoder-name-compression
    label: >-
      VulnCheck Advisory: Hickory DNS hickory-proto 0.3.1 before 0.26.1 CPU
      Exhaustion via BinEncoder Name Compression
tags:
  - cve.org
ingestedAt: '2026-11-08T02:43:18.639Z'
---

## Overview

Hickory DNS hickory-proto from 0.3.1 before 0.26.1 contains a denial of service vulnerability in BinEncoder that allows remote attackers to exhaust CPU through quadratic-time name compression. Attackers can send malicious DNS messages with many records that add many candidate labels and trigger repeated linear scans during encoding, amplifying CPU exhaustion.

## Affected

- `hickory-dns >= 0.3.1 < 0.26.1`

## Remediation

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