Upstream information

CVE-2026-81634 at MITRE

Description

In NLnet Labs Unbound up to and including 1.26.0, a 255 length query name with a large TCP response can lead to a heap buffer overflow during the RRSet canonicalisation routine. This is caused by missing to add the first owner name into the buffer length check. A malicious actor operating a malicious name server or tampering with an incoming response to Unbound (canonicalisation happens before DNSSEC validation), can trigger the vulnerability.

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having important severity.

CVSS v3 Scores
CVSS detail CNA (NLnet Labs) SUSE
Base Score 7.5 8.1
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector Network Network
Attack Complexity Low High
Privileges Required None None
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact None High
Integrity Impact None High
Availability Impact High High
CVSSv3 Version 3.1 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 9.2
Vector CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Attack Vector Network
Attack Complexity High
Attack Requirements None
Privileges Required None
User Interaction None
Vulnerable System Confidentiality Impact High
Vulnerable System Integrity Impact High
Vulnerable System Availability Impact High
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
CVSSv4 Version 4.0
SUSE Bugzilla entry: 1280409 [NEW]

SUSE Security Advisories:

List of released packages

Product(s) Fixed package version(s) References
SUSE Liberty Linux 10
  • python3-unbound >= 1.24.2-7.el10_2.6
  • unbound >= 1.24.2-7.el10_2.6
  • unbound-anchor >= 1.24.2-7.el10_2.6
  • unbound-devel >= 1.24.2-7.el10_2.6
  • unbound-dracut >= 1.24.2-7.el10_2.6
  • unbound-libs >= 1.24.2-7.el10_2.6
  • unbound-utils >= 1.24.2-7.el10_2.6
Patchnames:
RHSA-2026:71419 (x86_64)
SUSE Liberty Linux 8
  • python3-unbound >= 1.16.2-5.14.el8_10.4
  • unbound >= 1.16.2-5.14.el8_10.4
  • unbound-devel >= 1.16.2-5.14.el8_10.4
  • unbound-libs >= 1.16.2-5.14.el8_10.4
Patchnames:
RHSA-2026:70754 (i686,x86_64)
SUSE Liberty Linux 9
  • python3-unbound >= 1.24.2-3.el9_8.8
  • unbound >= 1.24.2-3.el9_8.8
  • unbound-devel >= 1.24.2-3.el9_8.8
  • unbound-dracut >= 1.24.2-3.el9_8.8
  • unbound-libs >= 1.24.2-3.el9_8.8
Patchnames:
RHSA-2026:71487 (i686,x86_64)
openSUSE Tumbleweed
  • libunbound8 >= 1.26.1-1.1
  • python3-unbound >= 1.26.1-1.1
  • unbound >= 1.26.1-1.1
  • unbound-anchor >= 1.26.1-1.1
  • unbound-devel >= 1.26.1-1.1
  • unbound-munin >= 1.26.1-1.1
Patchnames:
openSUSE-Tumbleweed-2026-11930


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Desktop 15 SP7 unbound Affected
SUSE Linux Enterprise Micro 5.5 unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 unbound Affected
SUSE Linux Enterprise Module for Package Hub 15 SP7 unbound Affected
SUSE Linux Enterprise Server 15 SP7 unbound Affected
SUSE Linux Enterprise Server 16.0 unbound Affected
SUSE Linux Enterprise Server 16.1 unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 unbound Affected
SUSE Linux Enterprise Server for SAP applications 16.0 unbound Affected
SUSE Linux Enterprise Server for SAP applications 16.1 unbound Affected
SUSE Linux Micro 6.0 unbound Affected
SUSE Linux Micro 6.1 unbound Affected
SUSE Linux Micro 6.2 unbound Affected
openSUSE Leap 16.0 unbound Affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP5 unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP4 unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP5 unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 unbound Affected
SUSE Linux Enterprise Server 15 SP4 unbound Affected
SUSE Linux Enterprise Server 15 SP4-LTSS unbound Affected
SUSE Linux Enterprise Server 15 SP5 unbound Affected
SUSE Linux Enterprise Server 15 SP5-LTSS unbound Affected
SUSE Linux Enterprise Server 15 SP6 unbound Affected
SUSE Linux Enterprise Server 15 SP6-LTSS unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 unbound Affected
Products past their end of life and not receiving proactive updates anymore.
SUSE CaaS Platform 4.0 unbound Affected
SUSE Enterprise Storage 6 unbound Affected
SUSE Enterprise Storage 7 unbound Affected
SUSE Enterprise Storage 7.1 unbound Affected
SUSE Linux Enterprise Desktop 15 SP1 unbound Affected
SUSE Linux Enterprise Desktop 15 SP2 unbound Affected
SUSE Linux Enterprise Desktop 15 SP3 unbound Affected
SUSE Linux Enterprise Desktop 15 SP4 unbound Affected
SUSE Linux Enterprise Desktop 15 SP5 unbound Affected
SUSE Linux Enterprise Desktop 15 SP6 unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP1 unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP2 unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP3 unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP4 unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS unbound Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 unbound Affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 unbound Affected
SUSE Linux Enterprise Module for Package Hub 15 SP3 unbound Affected
SUSE Linux Enterprise Module for Package Hub 15 SP4 unbound Affected
SUSE Linux Enterprise Module for Package Hub 15 SP5 unbound Affected
SUSE Linux Enterprise Module for Package Hub 15 SP6 unbound Affected
SUSE Linux Enterprise Real Time 15 SP2 unbound Affected
SUSE Linux Enterprise Real Time 15 SP3 unbound Affected
SUSE Linux Enterprise Real Time 15 SP4 unbound Affected
SUSE Linux Enterprise Server 15 SP1 unbound Affected
SUSE Linux Enterprise Server 15 SP1-BCL unbound Affected
SUSE Linux Enterprise Server 15 SP1-LTSS unbound Affected
SUSE Linux Enterprise Server 15 SP2 unbound Affected
SUSE Linux Enterprise Server 15 SP2-BCL unbound Affected
SUSE Linux Enterprise Server 15 SP2-LTSS unbound Affected
SUSE Linux Enterprise Server 15 SP3 unbound Affected
SUSE Linux Enterprise Server 15 SP3-BCL unbound Affected
SUSE Linux Enterprise Server 15 SP3-LTSS unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 unbound Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 unbound Affected
SUSE Manager Proxy 4.0 unbound Affected
SUSE Manager Proxy 4.1 unbound Affected
SUSE Manager Proxy 4.2 unbound Affected
SUSE Manager Proxy 4.3 unbound Affected
SUSE Manager Proxy LTS 4.3 unbound Affected
SUSE Manager Retail Branch Server 4.0 unbound Affected
SUSE Manager Retail Branch Server 4.1 unbound Affected
SUSE Manager Retail Branch Server 4.2 unbound Affected
SUSE Manager Retail Branch Server 4.3 unbound Affected
SUSE Manager Retail Branch Server LTS 4.3 unbound Affected
SUSE Manager Server 4.0 unbound Affected
SUSE Manager Server 4.1 unbound Affected
SUSE Manager Server 4.2 unbound Affected
SUSE Manager Server 4.3 unbound Affected
SUSE Manager Server LTS 4.3 unbound Affected
openSUSE Leap 15.3 unbound Affected
openSUSE Leap 15.4 unbound Affected
openSUSE Leap 15.5 unbound Affected
openSUSE Leap 15.6 unbound Affected
Products at an unknown state of their lifecycle.
SUSE Linux Enterprise Server for NVIDIA 16.1 unbound Affected


SUSE Timeline for this CVE

CVE page created: Thu Sep 17 16:08:10 2026
CVE page last modified: Thu Oct 1 18:48:20 2026