---
id: CVE-2019-25031
title: >-
  Unbound before 1.9.5 allows configuration injection in
  create_unbound_ad_servers.sh upon a successful man-in-the-middle attack
  against a cleartext HTTP session
summary: >-
  Unbound before 1.9.5 allows configuration injection in
  create_unbound_ad_servers.sh upon a successful man-in-the-middle attack
  against a cleartext HTTP session. NOTE: The vendor does not consider this a
  vulnerability of the Unbound softw…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-74
vendor: nlnetlabs
product: unbound
affected:
  - unbound < 1.9.5
  - debian_linux = 9.0
patched:
  - unbound 1.9.5
published: '2021-04-27'
updated: '2026-08-25'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2019-25031'
references:
  - url: 'https://lists.debian.org/debian-lts-announce/2021/05/msg00007.html'
    label: cve@mitre.org
  - url: 'https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/'
    label: cve@mitre.org
  - url: 'https://security.netapp.com/advisory/ntap-20210507-0007/'
    label: cve@mitre.org
  - url: 'https://lists.debian.org/debian-lts-announce/2021/05/msg00007.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20210507-0007/'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.01339
epssPercentile: 0.70049
ingestedAt: '2026-08-25T11:24:50.575Z'
---

## Overview

Unbound before 1.9.5 allows configuration injection in create_unbound_ad_servers.sh upon a successful man-in-the-middle attack against a cleartext HTTP session. NOTE: The vendor does not consider this a vulnerability of the Unbound software. create_unbound_ad_servers.sh is a contributed script from the community that facilitates automatic configuration creation. It is not part of the Unbound installation

## Affected

- `unbound < 1.9.5`
- `debian_linux = 9.0`

## Remediation

Upgrade past the affected range:

- `unbound 1.9.5`