CVE-2026-78301Out-of-zone database nodes can become authoritative zone cuts

A malformed zone may contain an NS or DNAME node above its origin, which `named` treats as a zone cut. If an attacker inserts a malformed zone into a BIND authoritative server (e.g., via zone transfer), queries for names inside the configured zone then lose authoritative status and return an out-of-zone delegation. On a server that also provides recursion BIND can follow this locally sourced cut and cache attacker-supplied data, affecting names outside the configured zone. This situation persists as long as the malformed zone remains in the zone database. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS

5.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:N

Weakness (CWE)

CWE-349

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

isc

NVD analysis

Awaiting Analysis

Record last updated

Sep 17, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.