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5.9Medium

Nlnetlabs Unbound

CVE-2019-25031

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

What this means for your business

  • It affects Nlnetlabs Unbound. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.

What to do

  1. 1Check whether your company or your suppliers run Nlnetlabs Unbound, and which version. The affected versions are listed further down this page.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

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Scoring

CVSS
5.9 (v3.1)
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness
CWE-74
Assigned by
cve@mitre.org

Dates

Published
2021-04-27
Last modified
2026-08-25
Sources
NVD

Affected products

  • Nlnetlabs Unbound- 1.9.5
  • Debian Debian Linux9.0

As listed in the NVD configuration data. Not a statement about your estate.

References