CVE-2026-78301: Bind9 · A malformed zone may contain an NS or DNAME node above its origin, which named treats as a
Affects bind9Source GCVE Database
Not known to be exploited · CVSS 5.8 Medium · fixed in 1:9.9.5.dfsg-3ubuntu0.19+esm15 : update bind9 when convenient.
Data as of 3 Nov 2026, 23:36 UTC
- Patch
- Available – fixed in 1:9.9.5.dfsg-3ubuntu0.19+esm15, 1:9.10.3.dfsg.P4-8ubuntu1.19+esm11, 1:9.11.3+dfsg-1ubuntu1.19+esm6 +5
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 3 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10bind9pkg:deb/ubuntu/bind9?arch=source&distro=stonkingOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSbind9pkg:deb/ubuntu/bind9?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSisc-dhcppkg:deb/ubuntu/isc-dhcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSbind9pkg:deb/ubuntu/bind9?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSisc-dhcppkg:deb/ubuntu/isc-dhcp?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSbind9pkg:deb/ubuntu/bind9?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and should be applied. Fixed versions include 1:9.9.5.dfsg-3ubuntu0.19+esm15, 1:9.10.3.dfsg.P4-8ubuntu1.19+esm11, 1:9.11.3+dfsg-1ubuntu1.19+esm6, 1:9.18.30-0ubuntu0.20.04.2+esm3, 1:9.18.39-0ubuntu0.22.04.7, 1:9.18.39-0ubuntu0.24.04.8, 1:9.20.24-1ubuntu3.1, and 1:9.20.24-1ubuntu0.4. Users and administrators should upgrade to these fixed versions to remediate the vulnerability. No vendor advisory states that no action is required or that the issue is already mitigated without patching.
Description
A vulnerability in BIND 9 allows a malformed zone containing an NS or DNAME node above its origin to be treated as a zone cut by the named server. This can cause queries within the configured zone to lose authoritative status and return out-of-zone delegations. On servers providing recursion, BIND may follow this locally sourced cut and cache attacker-supplied data affecting names outside the configured zone. The issue persists while the malformed zone remains in the zone database. This affects multiple BIND 9 versions and has a medium severity rating with a CVSS score of 5.8.