CVE-2026-109125: Unbound 0 to before 1.26.2

CVE-2026-109125. CVSS 3.1 base score 5.3 (MEDIUM, Vendor/CNA).

Affected technology

Unbound · 0 to before 1.26.2
NLnet Labs

Description’s affected range: up to and including version 1.26.1

Component: Not specified by the source

Attack conditions (Vendor/CNA, CVSS 3.1): Adjacent network · No privileges required · No user interaction required

What an attacker can do

In scenarios where the attacker can keep a concurrent query window alive, the attacker can first filter the source port and then perform birthday-style guessing against the TXID, making cache poisoning a feasible attack path. Vendor/CNA’s CVSS 3.1 assessment (base score 5.3/10) rates confidentiality and availability impact as none; integrity impact as high.

Published 21-Oct-2026 16:14 UTC

CWE: CWE-205
CCR priority: 21.2 /100 (P4)
CVSS 3.1: 5.3 /10 · CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N · Vendor/CNA
KEV: no

Provenance

GitHub Advisory Database · Source record · observed 2026-10-21 16:14:50.830645+00:00 UTC
NVD CVE API 2.0 · Source record · observed 2026-10-21 16:09:05.633125+00:00 UTC

Stable permalink: https://cybercodered.org/item/cve-cve-2026-109125.html